The 60-second answer
- What cost seg does. An engineering-based cost-segregation study reclassifies a rental property's basis from the default 27.5-year residential-real-property class life (§168(c)) into 5-, 7-, and 15-year component class lives (land improvements, personal property, specific building systems). The shorter-life components are eligible for §168(k) bonus depreciation in the year placed in service.
- Why it stacks with §469. Without the STR loophole, a cost-seg-generated rental loss is per-se passive under §469(c)(2) and gets suspended under §469(d)(1) until passive income appears. With the loophole (§1.469-1T(e)(3)(ii)(A) 7-day-average-stay test met per property + a §1.469-5T(a) material-participation test met), the rental is out of the per-se passive class and the loss is non-passive, offsetting W-2 or active-business income in the year of the deduction.
- OBBBA restored 100% bonus. The One Big Beautiful Bill Act (P.L. 119-21, July 2025) restored 100% §168(k) bonus depreciation permanently for qualified property acquired and placed in service after Jan 19, 2025. Property acquired before Jan 19, 2025 but placed in service later remains on the TCJA phase-out schedule (80%/2023, 60%/2024, 40%/2025, 20%/2026, 0%/2027). Confirm acquisition date with your CPA; it's the gating question.
- Look-back studies work. §446 and the method-change procedures in Rev. Proc. 2015-13 (as modified) together with the current automatic-change list in Rev. Proc. 2024-23 (DCN 7, change from impermissible to permissible method of accounting for depreciation of MACRS property) let you commission a cost-seg study for a prior-year property and recognize the cumulative accelerated depreciation on the current-year return via Form 3115 and a §481(a) adjustment, without amending prior returns.
- Recapture at sale is real. The 5-year personal-property components are §1245 property with full ordinary-income recapture to the extent of gain. The 27.5-year shell is §1250 straight-line, so no §1250 ordinary recapture, but the full shell depreciation is unrecaptured §1250 gain under §1(h)(6) at a max 25% rate to the extent of gain. The 15-year land improvements default to 150% declining-balance GDS, which does produce some additional-depreciation §1250 ordinary recapture (often small in practice; can be eliminated by ADS election). Cost seg accelerates deductions but doesn't make them permanent; the time-value-of-money and §469-W-2 offset is where the benefit comes from.
- Documentation on exam. The IRS Cost Segregation Audit Techniques Guide (most recently updated 2022) acknowledges the method. On an STR-loophole return with cost seg, the request on exam mirrors the 4-axis frame: engineering study + §469 material-participation log + §280A(d)(1) personal-use day count + §1.469-1T(e)(3)(ii)(A) average-stay calc.
Not tax advice; general framework. Material participation and depreciation elections are fact-specific IRS determinations; your CPA has the call on your specific facts. §168(k) rates reflect OBBBA as enacted; confirm current statutory treatment with your CPA before any decision.
What a cost-seg study actually does
Default MACRS treatment for residential rental under §168(c) depreciates the entire improved-property basis (purchase price minus land value) over 27.5 years straight-line. That means a $600,000 rental property with $100,000 of land value depreciates its $500,000 improvement basis at about $18,200 per year, every year, for 27 and a half years.
A cost-segregation study is an engineering analysis that identifies components of the property that qualify for shorter class lives under Rev. Proc. 87-56 and the §168 regulations:
Most STR furniture falls here under asset class 57.0 (Distributive Trades and Services) per Rev. Proc. 87-56: beds, sofas, dining sets, TVs, loose furnishings, carpet, decorative lighting, movable partitions, specific electrical for identified equipment. §1245 personal property.
Primarily owner's back-office equipment under asset class 00.11 (furniture and fixtures of a management office). Rarely a material slice of STR cost-seg because the rental unit's furniture is 5-year under 57.0.
Land improvements: driveways, walkways, fences, parking lots, landscaping, outdoor lighting, swimming pools, septic systems, exterior HVAC pads. §1250 class but shorter-life.
The structural shell: foundation, framing, roof, exterior walls, interior walls not specific to equipment, standard building HVAC, plumbing, electrical not reclassified above. Everything the study doesn't carve out stays in the default residential-rental class.
Typical outcomes for well-constructed STR properties: 15% to 25% of the improvement basis reclassifies into 5-, 7-, or 15-year classes. On the $500,000 example above, that's $75,000 to $125,000 of basis that was going to depreciate over 27.5 years and now either depreciates over 5 to 15 years, or (if §168(k) bonus applies at a non-zero percentage) depreciates substantially in year one.
§168(k) bonus depreciation under OBBBA: current state
§168(k) allows an immediate first-year deduction for a percentage of the basis of qualifying property placed in service in the year, in addition to the regular MACRS depreciation on the remaining basis. The TCJA set bonus at 100% through 2022 and then scheduled a 20-percentage-point annual decline. The One Big Beautiful Bill Act (P.L. 119-21), signed July 2025, interrupted that phase-out: it restored 100% bonus depreciation permanently for qualified property acquired and placed in service after January 19, 2025.
The practical effect: for most 2026-decision scenarios, 100% bonus is the applicable rate. The transitional-rule gap is property acquired before Jan 19, 2025 but placed in service after that date; that property remains on the TCJA phase-out schedule.
| Fact pattern | Applicable §168(k) bonus % |
|---|---|
| Acquired AND placed in service after Jan 19, 2025 (OBBBA, permanent) | 100% |
| Acquired on or before Jan 19, 2025; placed in service 2023 | 80% (TCJA) |
| Acquired on or before Jan 19, 2025; placed in service 2024 | 60% (TCJA) |
| Acquired on or before Jan 19, 2025; placed in service 2025 | 40% (TCJA; pre-Jan 19 PIS) |
| Acquired on or before Jan 19, 2025; placed in service 2026 | 20% (TCJA transitional) |
| Historical: 2017-2022 placed in service (post-TCJA) | 100% |
Table reflects §168(k) as modified by OBBBA (P.L. 119-21, July 2025) and the TCJA phase-out schedule for the pre-OBBBA transitional window. "Acquired" generally means binding contract date for purchase (specific acquisition rules apply; confirm with your CPA). Verify current statutory treatment with your CPA before any planning decision.
Only components with class lives of 20 years or less are bonus-eligible, which means the 27.5-year building shell gets regular MACRS straight-line regardless of the §168(k) percentage. The entire reason to commission a cost-seg study is to carve basis out of the 27.5-year class into bonus-eligible 5- and 15-year classes.
Hypothetical worked example (illustrative only; your facts will differ). Running the numbers for a post-Jan 19, 2025 OBBBA-eligible 100% case on a $500,000 improvement-basis example, assuming a cost-seg study reclassifies $100,000 into bonus-eligible components and the property is placed in service in January 2026 (mid-month convention applies to 27.5-year residential; the shell figure below assumes January placed-in-service):
Hypothetical; illustrative only. 27.5-year residential uses mid-month convention; placed-in-service month affects the shell figure materially. Your CPA models the exact numbers for your specific facts.
That ~$96,300 of accelerated deduction only reaches your W-2 or active-business income if the §469 loophole is also met per property. Without the loophole, the extra deduction is a passive loss suspended under §469(d)(1). Not tax advice; your CPA models the exact numbers for your facts.
Why §469 non-passive treatment is what unlocks the benefit
Depreciation is a cost whether or not you can use the deduction in the year of generation. §469 governs when you can use rental losses against other income:
- Default rental treatment under §469(c)(2): all rental activities are per-se passive regardless of participation. A cost-seg-generated loss is suspended under §469(d)(1).
- STR loophole escape under §1.469-1T(e)(3)(ii)(A): if the average rental period is 7 days or fewer per property, the activity is not a "rental activity" for §469 purposes. It becomes a trade-or-business activity subject to the general §469 material-participation test.
- §1.469-5T(a) material participation test: once out of the per-se passive class, the activity is non-passive if the taxpayer materially participates. Any of the seven §1.469-5T(a) tests qualifies; most STR hosts aim at (a)(1) more than 500 hours or (a)(3) more than 100 hours and not less than any other individual.
Both the 7-day-average-stay test and the material-participation test are per-property. A cost-seg study on a property that doesn't meet both ends up accelerating deductions into a suspended passive-loss bucket; the loss carries forward under §469(b) until future passive income or a qualifying disposition under §469(g), but doesn't offset W-2 in the current year. For an active W-2 earner looking to offset ordinary income, this is the wrong outcome.
The practical sequencing: before you commission a cost-seg study, confirm with your CPA that you can reasonably meet the §469 material-participation test on the specific property for the current tax year. A $5,000 engineering study produces no current-year benefit if the §469 math doesn't hold for that property. See our 100-hour vs 500-hour decision framework and year-long tracking walkthrough.
Look-back studies and Form 3115 for prior-year properties
A frequent question: "I bought the property three years ago; can I still do cost seg?" Yes. The §446 accounting-method-change procedures (Rev. Proc. 2015-13 for the general method-change framework, as modified, together with the current automatic-change list in Rev. Proc. 2024-23, DCN 7 for depreciation method changes on MACRS property) treat a shift from straight-line 27.5-year depreciation on a component to shorter-life accelerated depreciation on that component as a change of accounting method rather than an amendment to each prior-year return. The mechanics:
- Commission the cost-seg study in the current tax year.
- Compute the §481(a) adjustment: the cumulative difference between the depreciation that was actually claimed on prior returns (straight-line 27.5-year) and the depreciation that would have been claimed if the components had been correctly classified from the start (shorter class lives, with bonus depreciation applied at the §168(k) percentage in effect for the original placed-in-service year).
- File Form 3115 with the current-year return. The §481(a) catch-up adjustment is recognized in the current year.
- Prior-year returns do NOT need to be amended, which avoids reopening three or more statute-of-limitations windows under §6501.
For a property placed in service in 2022 and originally depreciated under the default 27.5-year residential class (no cost-seg study at acquisition), a 2026 look-back study with Form 3115 can reclassify basis to 5- and 15-year components and recognize the cumulative delta (including the 100% §168(k) bonus that was available for 2022 placed-in-service property) on the current-year return. For a loophole-qualifying STR with sufficient §469 material participation, this becomes a current-year non-passive loss offsetting W-2 income (subject to §465 at-risk limitations and §461(l) excess-business-loss limitations).
Form 3115 mechanics are not DIY-friendly; this is a CPA task. Expect your CPA to charge $500 to $2,000 for the Form 3115 preparation on top of the engineering-study cost.
Recapture at sale: what you pay back
Accelerated depreciation isn't permanent. When you sell the property, depreciation claimed is subject to recapture under §1245 and §1250, which the IRS taxes at ordinary-income or capped-25% rates depending on the character:
Personal-property components reclassified via cost seg. Depreciation taken is fully recaptured as ordinary income at sale to the extent of the gain. If you took $75,000 of accelerated depreciation on 5-year components and sell at a gain, up to $75,000 of that gain is taxed at your ordinary-income rate (top rate ~37% federal plus state). No capital-gain rate on the recaptured portion.
Residential rental shell depreciates straight-line under MACRS by construction, so §1250 "additional depreciation" is zero and there is typically no §1250 ordinary-income recapture. BUT the full depreciation taken on the shell is "unrecaptured §1250 gain" under §1(h)(6), taxed at a max 25% federal rate at sale to the extent of gain.
15-year land improvements default to 150% declining-balance under MACRS GDS (with switch to straight-line), which does produce some "additional depreciation" over straight-line, meaning §1250 can recapture a portion as ordinary income to the extent of gain. The ordinary-recapture portion is often small in practice because of the DB-to-SL switch, but it is not zero by construction. The remainder is unrecaptured §1250 gain at the 25% max rate. Taxpayers can elect ADS straight-line on these components to eliminate the §1250-additional-depreciation exposure, trading faster first-year deductions (under GDS) for cleaner sale-side recapture (under ADS). Your CPA models the trade-off.
The net economic question is time-value-of-money. A $100,000 current-year non-passive deduction (saving ~$37,000 at a 37% federal rate) is worth more than a $100,000 recapture at ordinary (37%) or capped-25% rates five, ten, or fifteen years later, discounted at whatever discount rate applies to your situation. For most STR hosts in the §469-loophole-qualifying tier, the arbitrage works out favorably even with recapture; the magnitude of the win narrows as hold period shortens.
§1031 like-kind exchanges can defer gain on real-property components if you're rolling into another real-estate investment, but post-TCJA §1031 excludes personal property, so the 5-year §1245 components reclassified via cost seg can still trigger §1245 recapture even on an otherwise-qualifying exchange. §121 primary-residence exclusion generally doesn't apply to rentals but there are hybrid-use scenarios. These are CPA-side conversations before you ever commission the cost-seg study.
When cost seg pays off (and when it doesn't)
Rule-of-thumb thresholds practitioners use:
- Purchase price $500,000 or more
- Study provider expects 15% to 25% of basis to reclassify (based on property type and amenities)
- You can clearly meet §469 material participation on the property for the current tax year
- You expect to hold the property 5+ years (longer holds amortize the recapture cost better)
- Current-year W-2 or active-business income is substantial enough to absorb the loss (subject to §461(l) EBL cap)
- Purchase price under $300,000 (study cost eats the arbitrage)
- §469 material participation isn't comfortably met on the property (loss is suspended, no current-year benefit)
- Property is being flipped or sold within 2 to 3 years (recapture arrives before the deduction amortizes)
- Low or no W-2/active-business income to absorb the loss
- Taxpayer is at or near the §461(l) excess-business-loss cap already
Your CPA should run the specific NPV model for your property, hold period, and income profile before you commission a study. The economics are property-specific and taxpayer-specific; no article can tell you whether cost seg pays off on your facts.
The exam-documentation package
The IRS Cost Segregation Audit Techniques Guide (most recently updated 2022) sets out what examiners look for in a cost-seg study: engineering methodology, documented component identification, chain of title and placed-in-service dates, and consistency with the §263(a) capitalization rules. The study itself is the first axis of the documentation.
For STR hosts claiming the stack (cost seg + §469 loophole), the examiner's request on exam typically mirrors the 4-axis frame we've built the rest of the Field Ledger content around, plus the engineering study:
Engineering firm's report with component-level reclassification, placed-in-service dates, basis allocations, references to supporting construction documents (blueprints, contractor invoices, appraiser's property breakdown). Reputable study providers produce this as a standalone deliverable; keep it with the tax year's records.
Contemporaneous participation log with dates, specific activity descriptions, hours, property. Reg. §1.469-5T(f)(4) permits proof "by any reasonable means"; Tax Court cases (Moss v. Comm'r T.C. Memo 2017-30; Pohoreski v. Comm'r T.C. Memo 2019-22) give less weight to year-end ballpark reconstructions. The §469 log is the single most-contested piece of a cost-seg + loophole return on exam.
Reservation-level data showing total rental days divided by number of individual stays. Must be 7 or fewer per property for the loophole exception to the per-se passive rule to apply. Export from Airbnb and other platforms, consolidated per property.
If personal use exceeded the greater of 14 days or 10% of rental days, §280A limits the loss, which can undo the cost-seg benefit even when §469 would otherwise permit it. §280A acts as a ceiling on top of the §469 non-passive treatment.
The depreciation deduction flows through Form 4562 (Depreciation and Amortization) and onto Schedule E Line 18. The §481(a) adjustment from a look-back Form 3115 goes on Schedule E Line 19. The cost-seg basis allocations should tie out to Form 4562's property-by-property detail.
See our deeper walkthrough at how to prove material participation to the IRS and what to expect on an STR loophole audit for the broader exam-mechanics context. Material participation is a fact-specific IRS determination that depends on your specific circumstances. Not tax advice.
Common failure modes
Field Ledger: records your CPA uses for the §469 side of the stack
Cost segregation is a CPA-and-engineer task; Field Ledger doesn't do the engineering study and doesn't compute depreciation. What Field Ledger does is produce the §469 material-participation log, the §1.469-1T(e)(3)(ii)(A) average-stay calc, and the §280A(d)(1) personal-use day count that your CPA uses to confirm the loophole math: the records that have to hold up alongside the engineering study on exam.
- Owner-side §469 material-participation hours per property, contemporaneous entries
- §1.469-1T(e)(3)(ii)(A) average-stay calc from the stays you log per property
- §280A(d)(1) personal-use days tracked per property (personal vs. repair/maintenance; the personal-use days template adds finer categories)
- Per-property Schedule E CSV export your CPA uses to tie out to Form 4562
For the §1.469-5T(a)(3) "not less than any other individual" prong, a first-class UI for logging non-owner participant hours (cleaner, handyman, co-host, manager, or spouse) is on the roadmap and not shipped today; hosts targeting (a)(3) keep that record separately. See our spouse-participation article and co-host and property-manager article. AI-assisted natural-language capture is the default landing experience on every plan; nothing is machine-asserted. Material participation is a fact-specific IRS determination that depends on your specific circumstances.
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Frequently asked questions
Does cost segregation only help if I qualify for the STR tax loophole?
Cost segregation helps on any rental property because it accelerates depreciation (§167, §168) by reclassifying components from the default 27.5-year residential-real-property class life into 5-, 7-, and 15-year class lives eligible for bonus depreciation under §168(k). The question is whether the accelerated depreciation can be used immediately against ordinary income. For most rentals, §469(c)(2) treats rental losses as per-se passive, so a cost-seg-generated loss is suspended under §469(d)(1) until passive income is generated or the property is disposed of. For STR hosts who meet both the §1.469-1T(e)(3)(ii)(A) 7-day-average-stay test and a §1.469-5T(a) material-participation test, the rental is out of the per-se passive class, and the loss is non-passive, available to offset W-2 or business income in the year generated. The stack is what makes cost seg most valuable for STR-loophole-qualifying hosts. Material participation is a fact-specific IRS determination that depends on your specific circumstances. Not tax advice.
What is bonus depreciation for 2026 and when does it zero out?
The One Big Beautiful Bill Act (P.L. 119-21, signed July 2025) restored 100% §168(k) bonus depreciation permanently for qualified property acquired AND placed in service after January 19, 2025. Property acquired on or before January 19, 2025 but placed in service after that date remains on the pre-OBBBA TCJA phase-out schedule (80%/2023, 60%/2024, 40%/2025, 20%/2026, 0%/2027). Historical: 100% applied to 2017-2022 under the original TCJA. Only components in 5- and 15-year class lives (identified by a cost-seg study) are eligible for bonus; the 27.5-year building shell is not. Acquisition date is the gating question for which rate applies; confirm with your CPA before any planning decision.
What does a cost-seg study typically cost, and when does it pay off?
Engineering-based cost-seg studies typically cost $3,000 to $10,000 depending on property complexity, size, and the study provider. The commonly-cited rule of thumb is that cost seg becomes economically worthwhile when 15% to 25% of the building basis can be reclassified into shorter-life components, which usually requires a purchase price of $500,000 or more for the economics to work out. For smaller properties, DIY cost-seg services exist at $500 to $1,500, but they produce less rigorous studies and are more likely to be contested on examination. Your CPA should model the net-present-value calculation for your specific property before you commission a study.
Can I do a look-back cost-seg study for a prior-year property?
Yes. §446 and the method-change procedures in Rev. Proc. 2015-13 (as modified), together with the current automatic-change list in Rev. Proc. 2024-23 (DCN 7, change from impermissible to permissible method of accounting for depreciation of MACRS property), permit a change of accounting method via Form 3115. This lets you catch up prior-year depreciation that was "allowable but not claimed" into a current-year §481(a) adjustment. This is how hosts who bought a property several years ago can commission a cost-seg study today and recognize the cumulative accelerated depreciation on the current-year return without amending prior returns. The Form 3115 mechanics are not DIY-friendly; this is a CPA task. For STR-loophole hosts, a Form 3115 §481(a) catch-up adjustment can produce a large current-year non-passive loss that offsets W-2 income (subject to §465 at-risk and §461(l) excess-business-loss limitations).
What happens to the accelerated depreciation when I sell the property?
Three recapture buckets at sale, each limited by actual gain. (1) 5-year personal-property components (reclassified via cost seg) are §1245 property with full ordinary-income recapture to the extent of the depreciation taken. (2) 27.5-year residential shell depreciates straight-line under MACRS, so §1250 ordinary recapture is zero; the full shell depreciation taken is unrecaptured §1250 gain under §1(h)(6) at a max 25% federal rate. (3) 15-year land improvements default to 150% declining-balance under MACRS GDS, which produces some additional-depreciation §1250 ordinary recapture (often small in practice because of the DB-to-SL switch; can be eliminated by electing ADS straight-line, which trades first-year speed for cleaner sale-side treatment). The timing arbitrage is still typically favorable because of the time value of money and the ability to offset non-passive income during ownership, but the recapture does mean the full benefit of accelerated depreciation isn't permanent. Consult your CPA on your specific hold period and expected sale-gain mix.
Does cost seg trigger an audit?
Cost seg studies are a well-established tax-planning technique and are not themselves a per-se audit trigger. The IRS has published guidance (IRS Cost Segregation Audit Techniques Guide, most recently updated 2022) acknowledging the method; what examiners look at is whether the study documentation supports the component reclassifications, whether the taxpayer actually met the §469 material-participation requirement in the year the accelerated depreciation was claimed non-passive, and whether the Form 3115 mechanics (if applicable) were correctly handled. On an STR return claiming the §469 loophole plus cost seg, the documentation package examiners typically request mirrors the 4-axis frame: the engineering study + the §469 material-participation log + §280A(d)(1) personal-use day count + the §1.469-1T(e)(3)(ii)(A) average-stay calc. Material participation is a fact-specific IRS determination that depends on your specific circumstances.
Related guides
- How to depreciate your Airbnb property: MACRS mechanics without cost seg.
- How to qualify for the STR tax loophole: the §469 eligibility framework.
- What counts as material participation for a short-term rental: the seven §1.469-5T(a) tests.
- 100-hour vs 500-hour test decision framework.
- How to prove material participation to the IRS: the 4-axis documentation frame.
- The reconstruction problem: why year-end log rebuilds fail.
- Spouse participation and the STR loophole: §469(h)(5) spousal aggregation.
- Co-host and property-manager participation: §1.469-5T(a)(3) non-owner hours.
- STR loophole with a full-time W-2 job.
- Year-end tax prep checklist: Oct-Dec 2026 / Jan-Apr 2027 month-by-month plan.
- Schedule E vs Schedule C: which form applies.
- Multi-property STR record-keeping: 2, 5, 10-property playbook.
- STR tax software comparison: specialist tools side-by-side.
Statutory sources
- IRC §167: depreciation deduction.
- IRC §168: MACRS; §168(c) class life tables; §168(k) bonus depreciation (as modified by OBBBA, P.L. 119-21, July 2025, restoring 100% permanently for qualified property acquired and placed in service after January 19, 2025).
- One Big Beautiful Bill Act, P.L. 119-21 (July 2025): legislation restoring permanent 100% §168(k) bonus depreciation for post-Jan 19, 2025 acquisition-and-placed-in-service property.
- Form 461 instructions / annual Rev. Proc. inflation-adjustment releases: current-year §461(l) excess-business-loss thresholds (figures indexed annually).
- IRC §263(a): capitalization rules distinguishing capital expenditures from deductible repairs.
- IRC §469(c)(2): per-se passive treatment of rental activities. §469(d)(1) suspended-loss carryforward. §469(g) qualifying disposition triggering unlock.
- Reg. §1.469-1T(e)(3)(ii)(A): 7-day-average-stay rule removing a property from the "rental activity" class.
- Reg. §1.469-5T(a): the seven material-participation tests.
- IRC §280A(d)(1): 14-day-or-10% personal-use ceiling. §280A(c)(5) income cap when the ceiling is crossed.
- IRC §1245: recapture of depreciation on personal property as ordinary income.
- IRC §1250: recapture on real property; §1(h)(6) unrecaptured §1250 gain at the 25% max rate.
- IRC §461(l): excess-business-loss limitation for non-corporate taxpayers.
- IRC §465: at-risk rules.
- IRC §446 and §481(a): accounting-method changes and catch-up adjustments. Rev. Proc. 2015-13 (as modified) for the method-change framework; current automatic-change list in Rev. Proc. 2024-23 (DCN 7, depreciation of MACRS property) for cost-seg method changes.
- Rev. Proc. 87-56: MACRS class life tables.
- IRS Cost Segregation Audit Techniques Guide (most recently updated 2022).
- IRS Publication 946: How To Depreciate Property.
- IRS Publication 527: Residential Rental Property.
The key takeaway
Cost segregation alone accelerates depreciation into shorter class lives; the §469 STR loophole is what turns that accelerated deduction into current-year W-2 offset instead of suspended passive loss. The stack is more powerful under OBBBA than it has been in years: 100% §168(k) bonus depreciation is restored permanently for qualified property acquired and placed in service after January 19, 2025. The Q4 action window is placed-in-service date (components in service by Dec 31 for current-year deduction), the transitional-rule gap for property acquired before Jan 19, 2025, and the Form 3115 look-back opportunity on prior-year properties. The right sequencing is CPA-first: confirm §469 material participation is achievable on the specific property, model the NPV with your hold period and recapture assumptions, then commission an engineering study if the math holds. Field Ledger produces the §469 log, the §1.469-1T(e)(3)(ii)(A) stay calc, and the §280A(d)(1) personal-use count that back up the loophole side of the stack; your CPA and the engineering firm handle the depreciation side. Not tax advice; your facts determine the outcome.