5 Best Comp Analysis Software for House Flippers 2027

The short answer: pick a flip-first comp tool

Comp analysis software pulls recently sold homes that resemble a target property, adjusts them for differences, and estimates an after-repair value (ARV) you can use to set an offer. For a house flipper who sets their own offers, the right category is a flip-first tool where every sold comp is visible and editable, not a raw data feed. A data API or an enterprise valuation product fits a team that has a developer to build the process and someone to own it after launch.

TL;DR: choose a flip-first tool with editable comps if you bid on deals yourself, and check 12-month cost and export terms before you commit to anything you plan to connect to a workflow.

Key Takeaways

• If you set your own offers, a flip-first tool with editable sold comps usually fits better than a valuation API.

• Monthly list prices vary widely across these tools, so compare the 12-month cost and the plan limits rather than the first month.

• A comp tool is only as good as your condition rules, and a tool that shows which comps it excluded is worth more than one that only shows an ARV.

• Fannie Mae's 12-month comp window is an appraisal standard. Use it as a starting point, and write down why you used any older sale.

• Confirm export or API details before you pay for any tool you plan to connect to an automated workflow.

• Keep a named person's sign-off on every offer, whichever tool you choose.

How we evaluated these tools

This is an informed buyer's guide built from public vendor pages, a mortgage-appraisal guideline and a quarterly flipping report. It is not based on hands-on use, and every figure below comes from a page we opened for this review. The weights in the table are our judgment for a flip buyer, not an industry or vendor standard.

The weights favor transparency over price because a defensible ARV decides whether a deal makes money, and the cheapest seat does not change that. Fannie Mae's appraisal guideline frames the same question for mortgage lending: Appraisal window: comps closed within 12 months according to Fannie Mae (2025 version). The guide calls that a target rather than a hard cutoff, and it allows older sales when market conditions limit recent ones, provided the appraiser explains why.

Scope: we included five tools whose pages we could open. PropStream is excluded because its pricing page returned errors during this review, so this article prints no PropStream price. Cotality is also excluded, because we found no investor-facing comp product with a published price.

Market context: why comp discipline matters now

ATTOM counted 77,991 flipped single-family homes and condos in the second quarter of 2026, about 6.2% of home sales, according to ATTOM (2026). Typical profit margin: 21.5% in Q2 2026 according to ATTOM (2026), down from 25.7% a quarter earlier. With margins narrowing, a small ARV error takes a bigger bite out of profit.

The table uses the comparisons printed in ATTOM's Q2 release. ATTOM's Q1 2026 release shows slightly different prior-quarter numbers, so do not mix figures from the two releases.

Average rehab spend: $79K per project in Q1 2026 according to Kiavi (2026), in a fix-and-flip survey run with John Burns Research and Consulting. Higher rehab budgets raise the stakes of a wrong comp, because a mismatched sale can hide a repair overrun until the offer is already made.

What each tool costs

Each plan below is listed with the price the vendor's pricing page shows, and each vendor's citation sits in the sentence that carries its figures.

DealCheck's Plus plan costs $10 a month according to DealCheck (2026), with the Starter plan at $0 and the Pro plan at $20 a month. The page shows a yearly option labeled "3 months free" without a yearly dollar figure.

FlipperForce's Solo plan costs $79 a month according to FlipperForce (2026), or $59 a month billed yearly. Its Teams plan is $199 a month and its Business plan is $499 a month on monthly billing.

RentCast's Foundation plan costs $74 a month according to RentCast (2026), with 1,000 requests included. Its free Developer tier includes 50 requests, and the Growth plan is $199 a month for 5,000.

HouseCanary's Basic plan costs $19 a month according to HouseCanary (2026) on monthly billing, or $190 a year. Its Pro plan is $79 a month, its Teams plan is $199 a month, and Enterprise is custom. The page says usage-based costs are billed monthly on top of the plan price.

Pricing checked October 19, 2026.

ATTOM's developer page lists no plan prices in the portion we read, so its production access is shown as Quote-based below.

The "12 months at monthly price" column is our arithmetic: monthly price times 12, before overage, add-ons or taxes. Annual prices appear only where the vendor printed a dollar figure.

Five tools compared

The matrix uses only what each vendor's pages state. "Not stated" means we did not find the feature on the pages we read, not that the tool lacks it.

Per-vendor profiles

Each profile names the buyer it fits, what it does not do, and the evidence we used. Where a claim has no figure, the link points to the page that carries it.

DealCheck: best for editing comps one deal at a time

DealCheck fits a solo flipper or small team that analyzes deals one at a time and wants to add, drop or edit sold comps before trusting the ARV. It gives two ARV figures. Its own estimate does not reflect comp edits, while a price-per-square-foot figure uses the comps you select, according to DealCheck (undated help article). The help article recommends the price-per-square-foot figure once you edit or add comps.

The comp limits do not match across DealCheck's pages. The pricing page lists up to 10 sales and rental comps on Plus, while the help article says upgrading unlocks a list of up to 20 recent sales comps. Confirm which limit your plan gets before you buy. Neither page we read describes an API.

Start on the free plan and test the comp list against one or two of your own past sales. Paid plans include a 14-day free trial, as the pricing page states.

FlipperForce: best for teams that want comps, rehab and deal tracking together

FlipperForce fits a flip team that wants comps, the after-repair value step and deal tracking inside one tool. The February 14, 2025 post on FlipperForce's blog describes a comps stats widget that calculates the low-to-high sale price range, the price-per-square-foot range and both averages once you select comps. The same post places the widget in Step 1, the After Repair Value step, of the Flip Analyzer.

The pricing page caps users and leads or projects, but it does not state comp or property caps. The blog post does not explain how comps are chosen or filtered. Ask for the full comp list on one of your past deals before you rely on the averages, because an average can hide a weak comp. The plans are tiered by user count, so count the people who will log in before you pick a plan. The page says every plan includes the deal analysis tools.

RentCast: best for a developer-led valuation API

RentCast fits a team with a developer who wants a valuation feed with comparables in the response. Its reference for the valuation endpoint documents price, priceRangeLow and priceRangeHigh fields, plus a comparables list with fields such as status, price, distance, daysOld and correlation, in the RentCast developer reference.

The pricing page lists "Valuation Estimates" as a feature, but the plan-level inclusion did not come through in our read, so confirm the endpoint is on the plan you buy. The API returns data, not a comp-editing screen, which means the review step lives in your own process. Budget for overage using the request counts in the table above, and store each response so you can show later how an ARV was built.

HouseCanary: best for a valuation product with a named comp tool

HouseCanary fits a buyer who wants a valuation product with a named comparables tool and an accuracy statement from the vendor. The products page lists a "Custom Valuation & Comp Tool" and an "Automated Valuation Report," and it reports a 2.7% median absolute error on valuations, with no date, according to HouseCanary (undated product page). The same page describes an AVM as an estimated sale price, not an appraiser's opinion of value.

The products page does not explain how comps are chosen or weighted. The accuracy figure is vendor-reported and undated, so treat it as a claim to check rather than a benchmark. Ask for a sample comp report on one past deal and compare its comps with what actually sold before you commit to an annual tier.

ATTOM: best for data-heavy builds and market benchmarks, not a comp screen

ATTOM fits a team building its own property-data product or pulling bulk market data, and it is a useful source for flip-market benchmarks like the Q2 2026 figures above. Its developer portal says a free trial account issues an API key, and only calls that return a successful response count toward monthly allowances. Its endpoint reference lists an AVM Detail path, attomavm/detail.

The developer page we read lists no plan prices, and its contact link is a placeholder, so budget requires a sales quote. Nothing we read describes a comp-editing screen, so ATTOM is a data source rather than a flip analyzer. Plan authentication, the AVM path, billing counts and a sandbox request before you write code.

Where a configured workflow fits

The real alternative for many flippers is not a single tool but a stack of Zapier, Make or n8n flows, or an in-house script. Those platforms can keep run histories, retries, error branches and audit evidence when someone configures them. For a worked look at a configured renewal process, see our insurance renewal workflow ROI analysis. The buyer still has to design and own idempotency so one address is not logged twice, set access controls for API keys, plan escalation, and maintain each branch when a vendor changes its API.

A proposed design from US Tech Automations could set retry rules and escalation owners before the first run, log every run, and route flagged rows to a named person. The homepage describes a managed service in which the team maps, designs, builds and monitors each workflow, so the trade is between your own upkeep and a service contract. Confirm the export and API details for each comp tool during scoping, because the homepage does not describe them.

Proposed, configurable workflow, not a live deployment: the trigger is a new row in a Google Sheets deal tracker that holds the address, bedroom count, bathroom count and square footage. The action calls the valuation endpoint of the comp source you chose, such as RentCast's, with those subject fields, then writes the estimate, the price range and the comparable count back to the same row. The output is a comp summary plus a needs-review flag when the price range is wide or the comparable count is low. Prerequisites are an API key on a plan that includes the endpoint, Google Sheets access, and a field map agreed before the first run. The same field-mapping discipline appears in our workers' comp class code mapping guide. The human review point is a flipper who checks each comp's condition and removes non-flip sales before any ARV goes into an offer.

Second configurable path, escalation: the trigger is a flagged row that no one has reviewed after a period you set. The action sends a Gmail notice to the named deal owner with the row link and a run ID. The output is a logged decision, approved, revised or dropped, with a timestamp and the inputs used, which gives you an audit trail. Prerequisites are Gmail access and a named owner for each deal. The human review point is the owner, who signs every offer, and the workflow never sends one.

When NOT to use US Tech Automations

Skip a managed build if you close only a few deals a year and one entry-level comp plan covers your comps. Skip it if you need a visual comp grid for a lender, because a flip-first tool already produces that view. And skip it if your comp source has no API or export, since a workflow cannot move data you cannot extract. In those cases one comp tool and a shared spreadsheet are the simpler answer. For another example of weighing a platform choice against a custom build, see our dental membership platform guide.

Worked example: 1,400 screens a month

Take an illustrative two-person team that screens 1,400 addresses a month before choosing which houses to walk. At the RentCast Foundation price shown above, the first 1,000 requests are included, so the other 400 cost $0.06 each: $74 + (400 × $0.06) = $98 a month, or $1,176 a year. The Growth plan at $199 a month includes 5,000 requests and covers the same 1,400 with no overage, at roughly twice the monthly cost. That math assumes the plan includes the valuation endpoint, which the RentCast pricing page did not confirm for each plan. An ATTOM build would start from the propertyapi/v1.0.0 version path and the attomavm/detail AVM endpoint, but its production access is quote-based, so the annual cost is unknown until a sales quote arrives.

Who this is for

This fits solo flippers and small teams who set their own offers and want to read every comp. A developer-led team that wants a valuation feed should look at RentCast or ATTOM, and build a review step around it. A lender-facing appraisal is not a job for any tool in this list, and it needs a licensed appraiser.

Red flags: you need a lender-grade appraisal from software alone; you have no one to own API keys and data changes; you expect any tool to judge renovation condition for you.

Terms you will see in comp reports

• Comparable sale (comp): A recently closed sale of a home similar to the one you are valuing.

• After-repair value (ARV): The estimated value of a property once the planned renovation is complete.

• Automated valuation model (AVM): A model-based estimate of value that does not include a physical inspection.

• Price-per-square-foot ARV: A value built by applying the average price per square foot of selected comps to the subject home's living area.

• Condition adjustment: A correction for differences in finish, age or repair state between a comp and the subject home.

• Rehab budget: The estimated cost of the planned renovation, used to set the offer.

• Maximum allowable offer: The highest purchase price that still leaves room for the rehab budget and your profit target.

Decision checklist

1. Write your condition rule for comps, such as renovated homes with similar finishes, before you open any tool.

2. Ask the vendor which plan includes the comp list, ARV method or endpoint you need.

3. Pull one past flip and check whether the tool's ARV and comp list match what actually sold.

4. Confirm the export format and any API limits before you connect anything.

5. Compare the 12-month cost and the user or request limits, not the first month.

6. Name one person who signs off on every offer.

Questions flippers ask before they buy

Is a free comp tool enough for a first flip?

Often yes, for a first deal, if the free view lets you check the sold comps behind your ARV. DealCheck's free plan caps that view, so test its comp list on one past sale before you rely on it.

Can an AVM replace sold comps?

No. An AVM is a model estimate that does not see the renovation you plan, so use it to screen addresses and then check the ARV against sold comps you can read.

Does the Fannie Mae 12-month rule apply to flips?

Not directly. It is an appraisal guideline for mortgage lending, but it gives a sensible starting window. Document any older comp you use and the reason for it, as the guideline asks appraisers to do.

Which tool gives the most reliable ARV?

None of the pages we read shows an independent accuracy test for flips. The only accuracy claim is HouseCanary's vendor-reported, undated median error, so ask each vendor for a sample comp report on one of your past deals.

Do I need an API?

Only if someone on your team will own the API keys, the field map, the failed calls and the changes when a vendor updates its service. Without that owner, a comp tool with export and a shared spreadsheet is the safer choice.

Choosing and next steps

Start with the category. Choose a flip-first tool with editable comps if you bid yourself, a valuation API if a developer will own the integration, and a data provider only when bulk coverage justifies a quote. Compare the 12-month cost, the export terms and the limits on the plan you would actually buy. If you plan to connect comps to a workflow, see how US Tech Automations configures this and confirm the prerequisites in writing before you build.