How a Real Estate Investor Rebuilt Missing Cost Basis Records Before a Sale
Sam's List Editorial | 2026-08-16
This is an illustrative composite, assembled from patterns that recur in long-hold rental sales. It does not describe a specific client and the numbers are hypothetical.
An investor decided to sell a duplex she had owned for fourteen years. Her question to a CPA was simple: what will I owe?
The honest answer was that nobody could say yet, because her rental property cost basis records stopped somewhere around year six. She had the closing statement from the purchase, four years of organized receipts, and then a decade of improvements she remembered clearly and could not document at all.
Every undocumented dollar of improvement is a dollar of gain she would pay tax on.
Why Basis Goes Missing on a Long Hold
Basis erodes through ordinary life, not carelessness.
Owners change bookkeeping systems and the old file never migrates. A property manager handles the roof and sends a monthly statement that nets the cost against rent, so the improvement never appears as an asset. A refinance produces a new loan and everyone assumes the paperwork lives with the bank. A contractor is paid in cash for a bathroom, and fourteen years later there is nothing to point at.
Meanwhile the tax stakes grow. On a fourteen-year hold, appreciation plus accumulated depreciation can mean the taxable gain is a large multiple of anything the owner recognizes as profit.
Step One: Establishing What Actually Counts
Before hunting for documents, the work was deciding what to hunt for. Adjusted basis is roughly the original purchase price plus certain acquisition costs, plus capital improvements, minus depreciation allowed or allowable.
The line that matters most is repairs versus improvements. A repair keeps the property in ordinary operating condition and is deducted in the year paid. An improvement betters, restores, or adapts the property and gets capitalized and depreciated.
Practically: patching a roof section is usually a repair, replacing the entire roof is usually an improvement. Repainting a unit between tenants is a repair, gutting a kitchen is an improvement. Replacing a broken window is a repair, replacing every window in the building is closer to a restoration.
This mattered because she had been treating everything as a repair for years. Some of it should have been capitalized, and the ones that should have were exactly the ones with no paper trail.
Step Two: The Places Records Still Exist
The reconstruction pulled from six sources, in roughly this order of usefulness.
Closing statements. Both the original purchase and both refinances. The purchase settlement statement establishes the starting basis and separates the items that add to basis from the ones that do not. Title companies and closing attorneys frequently retain files longer than owners do, and requesting a copy is free.
County permit records. This was the most valuable find. Permits for the roof and the renovation existed in the county's online system with dates, scope descriptions, and contractor names. A permit does not prove what something cost, but it proves the work happened, when, and what it was, which turns a memory into a documented event.
Contractor and vendor records. With names from the permit file, two of the three contractors were still in business and could produce old invoices. The third had closed. Where 1099s had been issued, the amounts and payees were recoverable from prior filings.
Bank and credit card statements. Most banks provide seven years, sometimes more on request. Statements do not describe the work, but paired with a permit date they corroborate the amount well.
Insurance claim files. A hail claim from year nine included an adjuster's scope of loss listing damaged and replaced components, which is unusually good documentation of both timing and value.
The county assessor's improvement history. Assessors often record substantial improvements because they change the assessed value. It is corroborating evidence, not proof of cost.
What could not be recovered stayed out. Two projects paid in cash with no permit and no bank trail were left off entirely, because claiming a number you cannot support is not a strategy, it is an exposure.
Step Three: The Recapture Rule That Surprises Owners
Then came the part she had not budgeted for.
Depreciation is recaptured on sale. For real property, unrecaptured Section 1250 gain is generally taxed at a maximum federal rate of 25 percent, above the long-term capital gains rate that applies to the rest of the gain.
The phrase that catches people is allowed or allowable. Basis is reduced by the depreciation you were entitled to take, whether or not you actually took it. An owner who never claimed depreciation does not avoid recapture. They pay it on depreciation they never got the benefit of, which is the worst possible version of the outcome.
She had claimed depreciation on the building, so this was arithmetic rather than a crisis. For an owner who has not, there is a separate conversation to have with a CPA about a change in accounting method on Form 3115, which in some circumstances allows missed depreciation to be corrected. Whether it is available, and whether it helps, depends on specific facts. It is a question to raise, not a fix to assume.
What Cleaner Records Changed
Two things, one of them not about tax at all.
The documented improvements raised her adjusted basis, which reduced the gain, which reduced the tax. The size of that effect depends entirely on what gets found, and in a reconstruction like this it can be modest or it can be significant. There is no way to know before the work is done, and no firm can promise a number in advance.
The second thing was the closing itself. Basis questions surface during diligence and at the settlement table, and an owner who can answer them in a day rather than a month keeps the timeline. Deals lose momentum in the gaps.
The other lesson is cheaper than the reconstruction: keep a running basis schedule for every property from the day you buy it. One spreadsheet per property, one line per capital improvement, with the date, the amount, the vendor, and a link to the invoice. Update it the week the work is done, when it takes four minutes.
Getting Help With the Reconstruction
This work sits between bookkeeping and tax, and it goes faster with someone who has done it before and knows which records to chase first.
Anomaly CPA is a Boston firm founded in 2018 that lists SMB owners, VC-backed startups, high net worth individuals, and real estate investors among its specialties.
No firm can recreate documentation that does not exist, and the outcome of any reconstruction depends on what the records support. What experience changes is the order of the search and the defensibility of what you end up filing.
You can compare accountants by specialty, location, and verified review count in the Sam's List accountant directory.
Frequently Asked Questions
What if I have no receipts for improvements to my rental property? Receipts are not the only acceptable evidence. County permit records, contractor invoices obtained directly from the vendor, bank and credit card statements, insurance claim files, and assessor improvement histories can all corroborate that work was performed and what it cost. Work that cannot be supported by any record should generally be left out.
How does depreciation recapture work when I sell a rental? Depreciation reduces your basis, which increases your gain on sale. For real property, that portion is generally unrecaptured Section 1250 gain, taxed at a maximum federal rate of 25 percent rather than the long-term capital gains rate. State treatment varies, so run both.
What if I never claimed depreciation on my rental? Basis is still reduced by depreciation allowed or allowable, so you can owe recapture on deductions you never took. A change in accounting method on Form 3115 may allow missed depreciation to be corrected in certain circumstances. Raise it with a CPA before you sell, because timing affects the options.
Which improvements add to my cost basis? Work that betters, restores, or adapts the property is generally capitalized and added to basis, such as a new roof, an addition, a full kitchen renovation, or new HVAC. Routine maintenance that keeps the property in ordinary operating condition, like repainting or patching, is generally deducted currently. The line is fact-specific, so document the scope, not just the cost.
About the author: Kimberly Green is the cofounder of Sam's List, where business owners and high earners find vetted CPAs, financial advisors, and fractional CFOs. She's met one-on-one with 400+ financial professionals and writes from the real data behind thousands of client-advisor matches. Ask her anything about finding an accountant - she's heard it all, including the questions people are afraid to ask.