The Journal
Field notes for residential investors and their CPAs, plain-spoken essays on the tax law, the methodology, and the strategy of accelerated depreciation for residential property.
Your rental’s placed-in-service date is not your closing date.
Closing settles ownership; it doesn’t start depreciation. The clock starts when the unit is ready and available to rent — and why a November date still front-loads on a $410K rental.
Read the essay →Wisconsin doesn’t allow bonus depreciation. Is a cost segregation study still worth it here?
The state decoupled from bonus in 2014 and never came back — but it still recognizes 5-, 7- and 15-year class lives. What that splits into on a $520K Milwaukee duplex.
Read the essay →Can a cost segregation study lower your estimated tax payment? Here’s how the timing actually works.
Quarterly estimated taxes come due four times a year, and a study finished before you file can shrink the January 15 true-up. The mechanics, the safe harbor rule, and a worked $450K example.
Read the essay →Buying a rental before year-end? Here’s the cost segregation timeline that actually works.
Close in Q4 and the study is the easy part — what decides whether the deduction lands on this year’s return is your placed-in-service date. The realistic timeline, and a worked $475K example.
Read the essay →Cost segregation and the QBI deduction: does accelerating depreciation shrink your Section 199A write-off?
A cost seg study can push a rental’s taxable income toward zero, shrinking or wiping out that year’s 20% Section 199A deduction. Here’s why that trade still wins, with a worked $460K example.
Read the essay →Can you take bonus depreciation on a used rental property? Usually yes, and here’s why.
Bonus depreciation isn’t a new-construction perk. A used rental bought from an unrelated seller qualifies for 100% bonus depreciation on its short-life components — the acquisition rule, the two real disqualifiers, and a worked $480K example.
Read the essay →Cost segregation on a property with an ADU: how the accessory unit changes your depreciation math
An ADU is its own asset for depreciation purposes, not a slice of the main house. How the acquisition-date rule works for a self-built ADU, what a study finds inside one, and a worked $210K example.
Read the essay →Is cost segregation worth it on a smaller rental? Where the math stops penciling.
Is your rental too small or too cheap to bother with a study? There’s no minimum property value — the deduction scales with your building basis. The three things that actually decide it, with a worked $235K single-family example.
Read the essay →Cost segregation when you house hack: the unit you live in changes the math.
Buy a 2-4 unit, live in one, rent the rest? The unit you live in is a personal residence and isn’t depreciable — but a study still accelerates the rental share, and it can take 100% bonus depreciation. A worked $600K fourplex example.
Read the essay →Cost segregation on inherited property: you get a stepped-up basis, but usually not bonus depreciation.
Inherit a rental and Section 1014 resets its basis to fair market value on the date of death — a fresh, usually larger basis to accelerate. Why a study still pays, but inherited property generally can’t take bonus depreciation. A worked $700K example.
Read the essay →Cost segregation on a BRRRR or major renovation: how to accelerate the rehab dollars you just put in.
Did a BRRRR or gut renovation on a rental? Those capitalized rehab dollars are all building basis — no land to strip out — and they lean toward the short-life property a study accelerates into year one. A worked $150K example.
Read the essay →Cost segregation in an LLC or partnership: the deduction follows the basis, your K-1 decides who uses it.
Hold your rental in an LLC for liability protection? The entity doesn’t shrink or complicate a study — a single-member LLC is invisible to the math, and a partnership just splits the deduction across K-1s. A worked $600K example.
Read the essay →Cost segregation with a mortgage: your deduction follows the basis, not your down payment.
You put 20% down and the bank owns the rest — so is a study even worth it? Your depreciation is sized to the building’s basis, not your equity. Why a mortgage doesn’t shrink the write-off, with a worked $500K example.
Read the essay →Filed an extension on your 2025 return? There’s still time for a cost segregation study.
Your extended 2025 return isn’t final until it’s filed — which means a study can still land the full first-year deduction on it, no amending. The September 15 and October 15 runway, with a worked $475K example.
Read the essay →Cost segregation on new construction: can you run a study on a house you built, and is it worth it?
Built it instead of buying it? A study still works — and new construction is often the cleanest one there is, because you have the actual build records instead of an estimate. How 100% bonus depreciation applies, and a worked $480K example.
Read the essay →Cost segregation and the partial disposition election: writing off the roof, HVAC, or kitchen you tore out.
Renovate a rental and the old roof, furnace, or kitchen you tore out still has un-depreciated basis — a partial disposition election lets you write it off now. How it works, why cost segregation makes it possible, and a worked $360K example.
Read the essay →Does your state follow federal bonus depreciation? Why your cost seg deduction can shrink on the state return.
Federal bonus gives a full year-one write-off — but many states decouple and add it back. What state conformity does to your cost seg deduction, why the reclassification still helps, and a worked $500K example.
Read the essay →Cost segregation on a mid-term rental: why the 30-day guest changes how you use the deduction.
Rents like a short-term rental, taxed like a long-term one. A 30-plus-day average stay fails the seven-day test, so the loss is passive — what a study still delivers on a mid-term rental, with a worked $520K example.
Read the essay →Cost segregation on a vacation home you use yourself: how personal-use days change the math.
You block off the beach condo two weeks a year and rent it the rest. Personal-use days decide whether a study creates a loss now or a carryforward — the Section 280A 14-day/10% rule, with a worked $600K example.
Read the essay →What a cost segregation study actually reclassifies: the 5-, 7-, and 15-year buckets in a residential rental.
Residential rentals crawl along a 27.5-year clock. A study moves qualifying components into 5-, 7-, and 15-year buckets — carpet and appliances, furniture, driveways and landscaping. Exactly what reclassifies, what never does, and a worked $500K example.
Read the essay →Land value allocation and cost segregation: why the land split sets your ceiling.
Land isn't depreciable, so the land-versus-building split sets the ceiling on everything a study can accelerate. How to support a defensible allocation instead of defaulting to the assessor ratio, with a worked $500K example.
Read the essay →Cost segregation after a 1031 exchange: how the carryover-basis split changes the math.
A like-kind exchange splits your replacement property into carryover basis and excess basis, and only the excess basis is bonus-eligible. What a study can and can't accelerate after an exchange, with a worked $480K example.
Read the essay →Converting your home to a rental: does cost segregation still pay?
You convert a former home to a rental, run a study, and expect the 100% write-off, then learn the acquisition-date rule says otherwise. Why bonus usually will not apply to the building, what a study still accelerates, and a worked $360K example.
Read the essay →Cost segregation for passive investors: what happens to the losses.
No REPS, no STR loophole, so the deduction can't touch your W-2. But suspended passive losses aren't lost: they bank on Form 8582, absorb passive income while you hold, and release in full when you sell. A worked $450K example.
Read the essay →Real estate professional status: who qualifies, and what it unlocks.
The STR loophole gets the attention, but long-term landlords have their own path to using cost-seg losses against W-2 income: real estate professional status. The 750-hour test, the grouping election, and a worked $640K example.
Read the essay →Depreciation recapture: what happens when you sell.
“Doesn't the IRS just claw it all back?” Not quite. Cost seg concentrates recapture in the reclassified slice — §1245 personal property, with land improvements under the §1250 rules — and it's the slice a step-up can erase, and good exit planning can defer. The two rates, with a worked $525K example.
Read the essay →What documents do you actually need for a cost segregation study?
A residential study runs on a handful of documents you already have, the settlement statement, the land/building split, and your depreciation schedule. The full list, why each matters, and why there's no site visit.
Read the essay →Should you do a cost segregation study the year you buy, or wait?
The default is the first year the property is placed in service, but waiting can make sense. The time-value math, the exceptions, and how to decide.
Read the essay →Bonus depreciation vs. Section 179 for residential rentals.
Both expense rental assets up front, but only bonus depreciation can create a loss, while Section 179 caps out at your business income. The rule that decides which fits, with a worked $92K example.
Read the essay →Material participation for a short-term rental: the documentation to keep.
The STR strategy lives or dies on material participation. The 100-hour and 500-hour tests, the catch where your cleaner's hours count against you, and the contemporaneous log that holds up, with a worked $55K example.
Read the essay →The five short-life assets STR owners almost always under-claim.
Furniture, appliances, decor, technology, and the hot tub out back are 5- and 15-year property, and most STR owners leave them on the 27.5-year clock. The five most-missed, with a worked $74K example.
Read the essay →Cost segregation on a duplex or small multifamily: the numbers.
A duplex usually reclassifies more of its basis than a single-family, and the study costs the same flat fee. A worked $685K example, the per-unit math, and when it pencils.
Read the essay →Is cost segregation an audit risk? Audit-ready vs. audit-proof.
No study is “audit-proof”, and the word is a red flag. What audit-ready actually means, why a study doesn't by itself raise your odds, and the documentation that holds up if the IRS asks.
Read the essay →What a cost segregation study actually costs for a residential rental.
Real pricing on a residential study, why it costs far less than a five-figure commercial one, and a dollar-by-dollar look at whether the fee actually pays for itself.
Read the essay →Do you really need a site visit for a residential cost segregation study?
For most 1-4 unit rentals and STRs, a physical walk-through isn't required and rarely changes the result. What we use instead, and why the study is still audit-ready.
Read the essay →A CPA's quick reference: when residential cost segregation is worth recommending.
The four variables that decide whether a study pencils (basis, marginal rate, holding period, and usability) a property-value rule of thumb with a worked example, and the cases where it's better to skip it.
Read the essay →The short-term rental loophole, explained without the YouTube fluff.
A long-standing IRC §469 rule lets STR owners deduct cost-seg losses against W-2 income, if material participation holds up. Here's what the YouTube version glosses over.
Read the essay →100% bonus depreciation is back. Here's what it means for your next residential acquisition.
The OBBB restored 100% bonus depreciation for property acquired (contract signed) after January 19, 2025. Here's how it changes the math.
Read the essay →