"How to estimate ARV and pull comps like you mean it"

What ARV actually is

ARV is what a property will sell for after it's renovated, in finished condition, given current market values. It is not what the property is worth today as a fixer-upper, and it is not the seller's asking price.

Because the property doesn't exist in finished form yet, you can't look up its value. You estimate it from comps: recently sold homes that are similar to what your property will be once the work is done. That last part matters. For ARV, you comp against renovated houses, not other fixer-uppers.

Step 1: Pick comps that actually compare

A comp is only useful if it's genuinely similar to your subject property. Five rough criteria, in rough order of importance:

Recency. Use sold listings, not active ones, and keep the window tight. Sales in the last 3 months are ideal. Six months is a stretch. Anything older than that is describing a different market. Active listings tell you what sellers hope to get, which is not the same as what buyers paid.

Location. Same subdivision is best. Same submarket and same school zone is acceptable. Once you cross a major road, a school boundary, or into a different neighborhood, the comp gets weaker fast. Two houses a mile apart can sell for very different prices.

Size. Stay within roughly 20% of your subject's square footage. A 1,500 square foot house and a 1,450 square foot house compare cleanly. A 1,500 and a 2,400 do not, even on the same street.

Beds and baths. Match the count. A 3 bed / 2 bath comps against other 3/2 homes. A comp with a different count can still be used, but it needs an adjustment, which we'll get to.

Condition and age. For ARV you want renovated comps, since you're estimating finished value. Similar year built helps too, because a 1960s house and a 2015 house carry different buyer expectations even at the same size.

You're aiming for 3 to 5 comps that pass these checks. More than that and you're usually reaching for properties that don't really compare. Fewer than 3 and you don't have enough to spot an outlier.

Step 2: The price-per-square-foot method

Once you have your comps, the most common way to turn them into an ARV is price per square foot.

For each comp, divide its sale price by its square footage. That gives you a dollars-per-square-foot figure. Do that for every comp, average the figures, and multiply the average by your subject property's square footage.

The reason you don't just average the sale prices directly is that the comps are different sizes. Price per square foot puts them on a common footing so size differences don't throw the estimate off.

This method has one weakness. It treats every square foot as equal, and it ignores features. A comp with an extra bathroom or a finished garage will show a higher price per square foot, and that has nothing to do with size. Which is why the next step exists.

Step 3: Adjust for superior and inferior features

Adjusting is how you correct for the things price per square foot can't see. The rule is simple once you get the direction right.

If a comp has a feature your subject property won't have, the comp is superior. Subtract the value of that feature from the comp's sale price, so the comp is brought down to your subject's level.

If a comp is missing a feature your subject property will have, the comp is inferior. Add the value of that feature, bringing the comp up.

The direction trips people up, so hold onto the logic: you are adjusting the comp to look like your subject, not the other way around. Superior comp, adjust down. Inferior comp, adjust up.

Common adjustment items are an extra bedroom or bathroom, a garage, a finished basement, a pool, lot size, and a recent major system like a new roof or HVAC. Adjustment values vary by market, and getting exact figures takes local knowledge or an agent's help. The point is to make a reasonable, consistent correction rather than to pretend two unequal houses are equal.

Running one example all the way through

Here's an illustrative property to show the steps in action. Every number below is made up for teaching. Your real comps and values will be different.

Subject property: a 3 bed / 2 bath single-family house, 1,500 square feet, that you plan to renovate. When the rehab is done it will be a clean, updated 3/2 with an attached garage.

We pull three recently sold, renovated comps from the same subdivision:

Comp	Sold price	Size	Beds / baths	Notes	Sold
Comp 1	$295,000	1,480 sqft	3 / 2, attached garage	Renovated. Closely matches the finished subject.	6 weeks ago
Comp 2	$318,000	1,540 sqft	3 / 2, attached garage	Renovated, plus a finished sunroom and new landscaping.	2 months ago
Comp 3	$278,000	1,460 sqft	2 / 2, attached garage	Renovated, but one fewer bedroom.	3 months ago

Now the adjustments:

Comp 1 matches the finished subject closely. Same bed and bath count, same garage, similar size, sold recently. No adjustment. Adjusted price stays at $295,000.

Comp 2 has a finished sunroom and upgraded landscaping that the subject won't have. That makes it superior, so we subtract the value of those extras. Call it $12,000. Adjusted price: $318,000 minus $12,000, which is $306,000.

Comp 3 has one fewer bedroom than the finished subject. That makes it inferior, so we add back the value of a bedroom. Call it $14,000. Adjusted price: $278,000 plus $14,000, which is $292,000.

With adjusted prices in hand, convert each to price per square foot:

• Comp 1: $295,000 ÷ 1,480 = $199.32 per sqft
• Comp 2: $306,000 ÷ 1,540 = $198.70 per sqft
• Comp 3: $292,000 ÷ 1,460 = $200.00 per sqft

The three figures cluster tightly, between $198.70 and $200.00. A tight cluster is a good sign. It means the comps agree, and the estimate is on solid ground. The average is $199.34 per square foot.

Apply that to the subject's 1,500 square feet: 1,500 × $199.34 = $299,013.

Round to a clean, slightly conservative number and call the ARV $299,000. Rounding down a little rather than up keeps the estimate honest, since an ARV that's too optimistic is the more expensive mistake.

Step 4: From ARV to a maximum offer

ARV on its own doesn't tell you what to pay. To get there, flippers use the 70% rule.

The 70% rule says you should pay no more than 70% of the ARV, minus the cost of repairs:

Max offer = (ARV × 0.70) − repair costs

The 30% the rule holds back is meant to cover holding costs, closing and selling costs, and your profit. It is a rule of thumb, not a law. Some investors in competitive markets work off 75%, and some use a lower percentage when costs run high. Treat 70% as a sensible starting point.

For our example, say the renovation is estimated at $45,000. With an ARV of $299,000:

Max offer = ($299,000 × 0.70) − $45,000
          = $209,300 − $45,000
          = $164,300

So $164,300 is the most you'd pay for this house and still have the 70% rule's cushion intact. If the seller wants $185,000, the deal doesn't work on these numbers, and now you know that before you've spent a dollar.

Notice how much weight the ARV and the repair estimate carry. If your ARV were off by $20,000, your max offer moves by $14,000. If the rehab runs $15,000 over, your real margin shrinks by the same amount. The 70% rule is only as good as the two numbers you feed it, and ARV is the bigger of the two.

Where comping goes wrong

A few habits that produce bad ARVs, worth checking yourself against:

Using active listings instead of sold ones. Asking prices are hopes. Sold prices are facts.

Reaching for comps that don't compare, because the good comps gave a number you didn't like. If you have to cross a school boundary or stretch to a house twice the size, the comp is telling you something. Listen to it.

Comping a finished ARV against fixer-upper sales. For ARV, the comps are renovated homes. Comp condition to condition.

Skipping adjustments because they take effort. An unadjusted average treats a house with a pool and a house without one as the same. They are not.

Trusting a single automated estimate. Online value tools are a fine sanity check and a poor source of truth. They don't know the property is mid-renovation, and they can't see the comps you can.

The honest part

ARV is an estimate, and a careful estimate can still be wrong. Markets shift, and a renovation can uncover a problem that changes the finished product. Real estate investing carries real risk, including the risk of loss. Do your own diligence on every deal, get local input where you can, and treat every number here as a method to learn, not a result to expect.

What good comping buys you is a defensible number and a reason behind it. That's the difference between making an offer and guessing at one.

If you'd rather not rebuild this comp analysis by hand on every listing you look at, that's part of what we're building Whoof for: faster first-pass screening so the full ARV work goes into the properties that have already cleared an initial look.