ARV Calculation: How to Use Real Comps Without Inflating Your Numbers

You find a beaten-up house and run the numbers on your phone. The Zillow estimate says $310k. You subtract $40k for repairs, land a $220k purchase, and suddenly you're looking at a $50k spread. Three months into the project, you realize the neighborhood actually sold at $275k last month, not $310k. You're now holding $35k in negative equity and a bathroom that will never get finished.

ARV—After Repair Value—is the make-or-break number in every fix-and-flip, BRRRR, or tax-deed deal. It's not a guess; it's the price a buyer will actually pay for your property when it's fixed. But most beginners don't calculate it. They wish it into existence.

Why ARV Matters More Than Your Repair Estimate

A repair budget can slip by 10%, 20%, even 50%. Contractors miss issues. Inspectors find mold. But your ARV is rigid—it's set by the market, and the market doesn't negotiate with your cash flow. If you overshoot your ARV by $30k, you don't just lose $30k of profit; you lose the entire deal. You become a landlord who can't sell and can't refinance. That's capital locked, not invested.

Professional investors treat ARV as the foundation, not the ceiling. Get it wrong, and everything above it collapses.

Sold Prices, Not Listings: The Critical First Step

A listing price is a hope. A sold price is a fact. If your target property is on the market for $300k but the last five homes in that neighborhood sold for $265k–$285k, the listing is irrelevant. The market has spoken. Start there.

Pull sold data from your county assessor's office, MLS records (if you have access through an agent), or public deed databases. You need at least three to five recent sales—ideally from the past 90 days for hot markets, 180 days for slower areas. "Recent" matters because neighborhood values shift. A sale from two years ago in a gentrifying block can mislead you upward; one from a declining area can mislead you downward.

• Check the county assessor's website for deed records and sale prices (free, public)
• Use Zillow, Redfin, or Realtor.com sold filters, but always verify with local records
• Ask a local agent for MLS comps—they're more granular than public sites and show list vs. sale price gap

The Three Adjustments Every Comp Needs

Raw sold prices are useless without context. A $280k sale two blocks away is only a comp if the house is similar to yours. Three adjustments matter: condition, size, and location—in that order of impact on investor deals.

Condition is where beginners blow it. If your comp sold as a "true cosmetic rehab" but your target is a "structural foundation repair with gut renovation," you can't use that price directly. The comp probably sold for $10k–$25k less per significant deferred item (foundation, roof, electrical, plumbing). If you're fixing everything, you can command a higher ARV, but only if you're comparing apples to apples—and your repairs are done to buyer standards, not investor minimum.

Size adjustments are straightforward: a $280k comp with 1,800 sq ft is worth less per square foot than a $280k comp with 2,200 sq ft in the same neighborhood. Most investors work with a price-per-square-foot band—if the comp is 400 sq ft smaller, subtract $8–$15 per sq ft (varies by market). If your property is larger, add accordingly.

Location within the neighborhood also shifts ARV. A house one block from a school or park can sell 5–10% higher than one four blocks away. A corner lot near a main road can sell 5–10% lower. These are small tweaks, but they compound. Write them down.

Five Comp Mistakes That Inflate ARV

• Using list price instead of sold price—list is what the seller hoped for, not what the buyer paid
• Mixing condition tiers—comparing your full-gut reno to a cosmetic-only flip, or vice versa
• Ignoring price-per-square-foot variance—a comp 15% smaller in a different neighborhood isn't a comp
• Relying on outdated sales (>6 months old in a moving market)—you're forecasting today's buyers, not last year's
• Cherry-picking the highest sale to avoid hard truth—picking the one $300k comp when four others sold at $275k is how deals fail

Build Your Comp Range: Three Numbers, Not One

Don't land on a single ARV. Land on a range: conservative, realistic, and optimistic. Your conservative ARV is the lowest recently sold price in your area, adjusted down for any deferred maintenance you're fixing (tightens buyer pool). Your realistic ARV is the midpoint after adjustments—this is what you use for your deal math. Your optimistic ARV is the high end, adjusted up only if your property has genuine buyer appeal (finishes, location perks) that recent comps didn't have.

For example: you identify five recent sales between $270k and $295k. After condition, size, and location adjustments, your comps cluster around $280k–$290k. Your realistic ARV is $285k. Your conservative ARV is $275k. Your optimistic is $295k. Run your deal analysis on the realistic number. Use the conservative number as your stress test—if you can't make money at $275k, you can't make money in that deal.

Document Your Work: The Comp Sheet That Saves You

Write down every comp. Address, sold price, sold date, square footage, condition notes, and your adjustments. Why? Because when the deal is six months in and you're stressed about carrying costs, you'll second-guess your ARV and talk yourself into overhauling the finishes to justify a higher price. A written comp sheet reminds you that the market set the price, not your ego. It also protects you if a partner or lender questions your math—you can show your work.

The Discipline: Protect Your Capital First

ARV calculation is not glamorous. It's not the part of the deal that feels like investing. But it is the part that decides whether you keep your capital or lose it. A $15k ARV mistake on a $200k deal is a 7.5% loss of your total cost—and your margin of error on repairs and carrying costs just vanished. Discipline in comp research is discipline in survival.

The best investors in small-deal markets don't rely on software to guess ARV. They walk neighborhoods. They know the recent sales personally. They adjust for condition and size out of habit. They treat a $285k realistic ARV as a ceiling, not a floor. That's how they stay in the game deal after deal.