How to calculate ARV without an appraiser

Last updated: May 12, 2026

An appraisal costs five hundred dollars and takes a week. Before you spend either, you should already know within five percent what the property will be worth fixed up. After repair value is the single number that decides whether a deal is a deal. Get it wrong by ten percent on a $300,000 ARV and your profit evaporates into your contractor's pocket. Here are three methods that work without paying a single fee.

Why ARV is hard

ARV is not a market price for the house you are looking at. It is the price the house will fetch after rehab, in a future window, in the condition of comparable finished homes. Most ARV mistakes come from comparing a finished product to active listings, not closed sales, or from pulling comps that crossed a school district line, or from ignoring time decay in a rising or falling market.

Method 1: the closed comp average

The traditional appraiser method, simplified. Pull three to six closed sales that match your subject after repair. Apply these filters in order.

• Closed within the last ninety days. Six months only if your area is thin.
• Within a half mile, and never across a railroad track, highway, or school district boundary.
• Square footage within ten percent above or below your subject.
• Same bed count. Bath count within one.
• Same property type. Do not mix a townhouse into single family comps.
• Renovated condition. Skip lipstick flips and obvious distressed sales.

Average the price per square foot of the three closest matches by bed, bath, and finish. Multiply by your subject's square footage. Trim five percent if your finishes will be one tier below the average comp, add five percent if you are above. That is your ARV.

Free sources. Redfin shows closed sale prices for every state where it is permitted, with filters that match these criteria. Zillow recent sales tab covers the rest. For non disclosure states like Texas, Kansas, and Utah, use the county GIS portal or the property appraiser site directly. Most county portals publish the sale price and deed date for every recorded transaction.

Method 2: the price per square foot regression

If you are operating in a market where finished comps are sparse, expand the radius and let the math do the filtering. Pull twenty closed sales in the last one hundred eighty days within one mile. Plot square footage on the horizontal axis and sale price on the vertical axis in any spreadsheet. Add a linear trendline. The intercept and slope give you a market specific formula.

Example. If your trendline is price equals 35,000 plus 165 times square footage, then a 1,400 square foot subject runs you 35,000 plus 165 times 1,400, equals $266,000. Discount it by the residual standard error if your spreadsheet reports one. This is the same technique that powers most automated valuation models. It works because outliers in either direction wash out when you have enough points.

Free sources. Redfin downloads the underlying data as a CSV from any map search. Hit the download all link at the bottom of the listings panel. You get up to 350 sales per query, addresses included.

Method 3: the rent multiplier sanity check

This method is for sanity checking, not primary valuation. In any given neighborhood and price tier, the ratio of rent to price stays inside a narrow band. If single family homes between 1,200 and 1,800 square feet rent for $1,600 to $2,000 and sell for $220,000 to $260,000, the gross rent multiplier is roughly 130 to 145.

Find the rent your subject would command after rehab. Pull three live rental comps from Zillow Rentals, Apartments dot com, and Rentometer free tier. Discount the average by five percent. Multiply your rent by the local GRM you calculated from comps. If your method 1 ARV is more than ten percent above this number, your comp set is probably contaminated by a hot pocket or a flipped house that overshot the market. Reconsider.

The free data stack that beats most paid tools

The three mistakes that ruin amateur ARVs

1. Using active listings as comps. A house sitting at $310,000 with no offers tells you nothing about value. It tells you what someone wishes they could get. Closed only.
2. Ignoring lot or layout differences. A 1,400 square foot ranch on a half acre is not the same product as a 1,400 square foot two story on a fifth of an acre. If the comp lot value differs by more than ten thousand, adjust dollar for dollar.
3. Trusting Zestimate or Redfin Estimate as your number. These are AVMs trained on broad data. Median error nationally hovers near three to seven percent, but at the individual property level errors of twenty percent are common, especially on rehabbed product. Use them as a third opinion, never as your primary.

Adjustments that actually move the number

Two homes with the same square footage in the same subdivision can sell for fifteen percent apart. Most of that spread is captured by a handful of adjustments that even amateur appraisers know to apply.

• Garage. One car attached adds roughly five to eight thousand. Two car attached adds twelve to eighteen thousand. Detached discounts about fifteen percent off the attached number. No garage on a single family in a suburban market is a noticeable hit.
• Basement. Unfinished basement adds about thirty percent of above grade price per square foot. Finished basement adds about sixty percent. Walkout adds another five percent on top of that.
• Bathrooms. A full bath addition is worth six to ten thousand. A half bath is worth three to five thousand. Do not add a third bath if the floor plan does not naturally accept one. The rehab cost will exceed the value gained.
• Lot premium. Cul de sac, wooded backyard, or larger than typical lot can add three to seven percent. Corner lot in a starter market is roughly flat. Lot backing to a busy street or commercial use is a five to ten percent discount.
• Pool. In Texas, Arizona, and Florida a pool adds about eight to twelve thousand. In the Midwest and Northeast a pool can be neutral or negative because of the maintenance liability.

Build your own adjustment table from your specific submarket. The figures above are starting points. If you find a clean pair of comps where one has a feature and one does not, the price gap is your true local adjustment for that feature.

How to be honest with yourself

If your method 1 and method 2 disagree by more than seven percent, your comp set is too thin or your neighborhood crosses a line you have not noticed. Walk the streets between your subject and each comp on Google Street View. If the housing stock changes meaningfully along the way, drop that comp. If you end up with fewer than three comps after filtering, expand your time window before your geography. A clean comp from one hundred fifty days ago beats a contaminated comp from last week.