HomePilot – Home Buying Co-Pilot for Zillow

Tracking since Apr 29, 2026.

Changelog

• May 6, 2026
  description

  HomePilot turns every Zillow, Redfin, and Realtor.com listing into a complete financial briefing — in seconds, without leaving the page.
  
  You see a list price. HomePilot shows you what you'd actually pay: the true monthly cost, whether the price is fair, how much room you have to negotiate, and what local laws apply to you as a buyer. Everything a buyer needs to make a confident offer — right in the side panel.
  
  TRUE MONTHLY COST BREAKDOWN
  
  The list price is a fiction. HomePilot shows you the real number:
  
  • Mortgage payment — calculated instantly from your down payment %, interest rate, and loan term
  • Property tax — pulled from the listing (actual figure, not guesswork)
  • Homeowner's insurance — estimated at 0.65% annually
  • HOA fees — extracted directly from the listing
  • PMI — automatically added if your down payment is under 20%
  • Maintenance reserve — the 1%/year cost buyers always forget
  • True Monthly Cost — the all-in number, clearly labeled
  
  Change your assumptions (down %, rate, loan term) and every number recalculates instantly. No spreadsheets, no manual math.
  
  DEAL SCORE — IS THIS PRICE FAIR?
  
  Every listing gets a Deal Score based on real signals:
  
  • Great Deal — priced meaningfully below Zestimate
  • Good Deal — below market with room to negotiate
  • At Market — fairly priced
  • Above Market — seller asking above Zestimate
  • Overpriced — significantly above estimated value
  
  The score pulls from Zestimate vs. list price, days on market, and price reduction history. You see the signal immediately, not buried in a spreadsheet.
  
  PRICE INTELLIGENCE
  
  • Zestimate vs. list price delta — exactly how far above or below market the property is priced
  • Days on market — with a Hot / Active / Cooling / Slow signal
  • Price per square foot
  • Price reduction count and history — know if the seller has already cut once, twice, three times
  • Full price history timeline — see every price change and listing event
  
  OFFER CALCULATOR
  
  Drag a slider to any offer price from 85% to 110% of list. Your monthly payment recalculates in real time. See exactly what offering $20,000 less — or $10,000 more — costs you per month over 30 years. Make your offer with clear numbers, not gut feelings.
  
  TRUE COST TAB — LONG-TERM OWNERSHIP
  
  • 5, 10, and 30-year total payments and equity projections
  • Value appreciation model at 3%/yr (historical US average)
  • Mortgage interest tax deduction estimate and effective after-deduction monthly cost
  • Closing cost estimator — itemized: loan origination, underwriting, appraisal, title insurance, escrow, recording fees, prepaid interest, property tax escrow, insurance prepaid, HOA setup, and state transfer taxes (NY, IL, PA, CO, and more)
  • Income required calculator — what gross annual income you need to qualify at 28% and 36% DTI
  • Rent vs. Buy analysis — is buying actually cheaper than renting equivalent housing? With break-even horizon
  
  LOCAL LAWS TAB
  
  HomePilot knows the real estate rules for your specific city and state:
  
  • Transfer tax — who pays, what rate, city vs. county split
  • Property tax rules — state-specific caps (California Prop 13, Florida Save Our Homes, Texas homestead, and more)
  • Required seller disclosures — what the seller must tell you by law
  • First-time buyer programs — city and state down payment assistance, grants, and low-interest loans (50+ cities covered)
  • HOA state law overview + a red-flag checklist (reserve fund health, pending litigation, restriction review, and more)
  
  NEGOTIATE TAB
  
  HomePilot reads the signals and tells you exactly how to approach your offer:
  
  • Recommended strategy — from "Move Fast, Offer at List" (hot market, great price) to "Negotiate Hard or Walk" (overpriced, slow market)
  • Suggested offer price range with dollar figures
  • What to ask for — closing cost credits, home warranty, seller-paid repairs, contingencies
  • Nearby comparable sales table — recently sold homes with $/sqft comparison
  • Word-for-word negotiation scripts for every scenario: countering a high price, responding to "we have other offers," asking for closing credits, escalation clauses
  • Seller tactics to recognize — phantom offers, artificial urgency, emotional anchoring, bait-and-switch repairs
  • Full inspection checklist — structural, systems, and exterior items to verify
  
  SELLER INTELLIGENCE
  
  If price history data is available, HomePilot estimates:
  
  • When the seller bought the property and for how much
  • Their estimated equity and remaining loan balance
  • Their gain vs. purchase price
  • Whether they have significant negotiating flexibility — or may be firm because they're close to their loan balance
  
  NEIGHBORHOOD TAB
  
  • Walk Score, Transit Score, and Bike Score — pulled directly from the listing
  • Nearby schools with GreatSchools ratings, school type, and grade levels
  • One-click Google Maps commute link from the property address
  
  SHIELD TAB — BUYER PROTECTION
  
  • Dynamic red flags detected from listing data — multiple price cuts, extended DOM, significant overpricing, unreviewed HOA
  • Pre-offer checklist — 10 things to verify before submitting any offer
  • Homebuyer scam awareness — wire fraud, deed fraud, predatory refinancing, phantom rentals (the scams that cost buyers the most)
  • Closing & escrow protection checklist
  • Questions to ask at every stage — before the offer, during inspection, before closing
  • Listing language red flags — the phrases in listing descriptions that signal problems
  
  SAVED HOMES
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  Save any analyzed property and compare them side by side. Price, monthly cost, down payment, interest rate, and deal score — across up to 20 saved listings. Useful when you're weighing two or three finalists.
  
  HOW IT WORKS
  
  Navigate to any listing on Zillow, Redfin, or Realtor.com
  HomePilot opens automatically in the side panel
  Click "Calculate Monthly Cost" — results appear in seconds
  Explore Costs, Local, Negotiate, Shield, and Saved tabs
  All analysis runs locally in your browser. Saved homes stay in Chrome's local storage on your device. The only data sent to our servers is your account and usage count. No property data, searches, or financial information is stored on our servers.
  
  PRICING
  
  Free — 5 analyses per month, no credit card required.
  
  Pro — $19.99/month — unlimited analyses, closing cost estimator, seller intelligence, comps table, income required calculator, saved homes comparison.
  
  SUPPORTED SITES
  
  • zillow.com/homedetails/...
  • redfin.com (all listing pages)
  • realtor.com/realestateandhomes-detail/...
  
  PERMISSIONS
  
  • activeTab / scripting — to read the listing page you're viewing
  • storage — to save your session and saved homes locally
  • sidePanel — to display the HomePilot panel
  • tabs — to detect when you navigate to a listing page
  
  HomePilot does not read any other tabs. It only activates on Zillow, Redfin, and Realtor.com listing URLs.

  HomePilot is a free home buying calculator and co-pilot for Chrome. It activates automatically on every Zillow, Redfin, and Realtor.com listing and shows you what the listing doesn't — your true monthly cost, a fair offer range, negotiation leverage, and closing cost estimates. All in a side panel, without leaving the page.
  
  Stop making offers based on the listing price alone. Know the full picture before you sign anything.
  
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  WHAT HOMEPILOT SHOWS YOU
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  ✅ TRUE MONTHLY COST CALCULATOR
  Most buyers focus on the purchase price and forget about everything else. HomePilot calculates your actual monthly cost: mortgage P&I, property tax, homeowner's insurance, HOA fees, PMI (if down payment is under 20%), and a 1% maintenance reserve. Adjust down payment percentage, interest rate, and loan term to see your real number instantly.
  
  ✅ PRICE VS. ZESTIMATE ANALYSIS
  Is the asking price fair? HomePilot compares the list price against Zillow's Zestimate and shows you the gap as a percentage. A home listed 12% above Zestimate is a different negotiation than one listed 3% below. See it in one number before you decide to tour.
  
  ✅ OFFER CALCULATOR & NEGOTIATION STRATEGY
  HomePilot scores each property on deal quality — factoring in price vs. Zestimate, days on market, price history, and list price trends. The offer calculator generates a fair offer range and negotiation strategy: how much room you have, what the seller's position likely is, and what to anchor your opening offer on.
  
  ✅ DAYS ON MARKET SIGNAL
  Days on market (DOM) is one of the most useful pieces of data on any listing, and most buyers ignore it. HomePilot interprets DOM in context: a home at 5 days is a different negotiation than the same home at 65 days. The panel shows you what DOM means for your leverage and how it relates to the local market average.
  
  ✅ CLOSING COST ESTIMATE
  First-time buyers are often blindsided by closing costs at the end of the process. HomePilot estimates your total closing costs — lender fees, title insurance, escrow, prepaid interest, recording fees, and more — so you can budget for the full purchase, not just the down payment.
  
  ✅ SELLER EQUITY ESTIMATE
  HomePilot estimates the seller's approximate equity based on public record data when available. A seller with high equity has more room to negotiate. A seller underwater may not be able to come down. Knowing this changes your offer strategy.
  
  ✅ SCHOOL RATINGS & WALK SCORE
  HomePilot surfaces school ratings and walk scores directly from the listing data — no extra clicks, no separate tab. See them alongside your monthly cost and deal score in one panel.
  
  ✅ PROPERTY HISTORY
  See the full price history for the property — how many times it's been listed, at what prices, and how long it sat each time. A home that's been relisted three times in two years at declining prices tells a story. HomePilot tells it automatically.
  
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  WORKS ON ALL MAJOR REAL ESTATE SITES
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  HomePilot activates automatically on:
  • Zillow (all /homedetails/ listing pages)
  • Redfin
  • Realtor.com
  
  Navigate to any listing page on these sites and HomePilot opens in Chrome's side panel — no clicking required.
  
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  WHO HOMEPILOT IS FOR
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  First-time home buyers: The home buying process is full of numbers nobody explains — PITI, PMI, escrow, DOM, Zestimate variance, closing costs. HomePilot explains all of it in plain language on every listing you look at.
  
  Move-up buyers: You know the process but you're comparing 15 listings across different price points and neighborhoods. HomePilot standardizes the analysis so you're comparing apples to apples.
  
  Budget-conscious buyers: The monthly cost calculator shows you the real number — the one you'll actually write a check for each month — so you don't fall in love with a house you can't afford.
  
  Investors and house hackers: The deal score and seller equity estimate give you a fast signal on negotiation room. Filter out the no-gos in seconds.
  
  Buyers' agents: Use HomePilot to run quick analysis for clients during tours without leaving the listing page.
  
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  FREE PLAN — NO CREDIT CARD REQUIRED
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  5 free property analyses per month. Every analysis includes:
  • True monthly cost breakdown
  • Price vs. Zestimate comparison
  • Offer calculator and deal score
  • Days on market signal
  • Closing cost estimate
  • Price history
  
  Upgrade to Pro for unlimited analyses — for active buyers comparing dozens of properties.
  
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  PRIVACY & DATA
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  All analysis runs locally in your browser. HomePilot reads data from the listing page you're already viewing — it does not make external property data requests, does not track your searches, and does not store any property data on our servers. Saved properties are stored in Chrome's local storage on your device. The only data sent to our servers is your account email and usage count.
  
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  FREQUENTLY ASKED QUESTIONS
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  Is HomePilot free?
  Yes. The free plan includes 5 full property analyses per month — no credit card required. Each analysis includes the true monthly cost calculator, price vs. Zestimate, deal score, offer calculator, and closing cost estimate.
  
  Which sites does HomePilot work on?
  HomePilot works on Zillow, Redfin, and Realtor.com listing pages. It activates automatically in Chrome's side panel when you navigate to any property listing on these sites.
  
  How accurate is the monthly cost calculation?
  Mortgage math is exact given your inputs (price, down payment, rate, term). Property tax uses the actual figure from the listing when available, otherwise estimates at 1.1% annually. Insurance is estimated at 0.65%/yr. Maintenance reserve uses the industry standard 1%/yr. Always verify with your lender's official Loan Estimate.
  
  What is the Zestimate comparison?
  Zillow's Zestimate is an automated home valuation. HomePilot shows you the percentage difference between the list price and the Zestimate — a quick signal of whether the seller is priced at, above, or below estimated market value.
  
  Is my browsing data private?
  Yes. HomePilot reads data from the listing page you're viewing and processes it locally. No property data, search history, or financial inputs are stored on our servers.
  
  What is the deal score?
  The deal score is a composite signal calculated from price vs. Zestimate, days on market, price history trajectory, and list price trends. It gives you a fast read on how much negotiation room the property likely has.
  
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  ABOUT EXTENSIONSMARKET
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  HomePilot is built by ExtensionsMarket (extensionsmarket.com), an independent software developer building browser extensions and Shopify apps that help people make better financial decisions. Other tools include CarWise (used car VIN decoder), STRInvest (short-term rental investment analysis), AirPrice (Airbnb pricing), MapLeads (B2B lead generation), and more.
  
  Questions or feedback: [email protected]

• May 6, 2026
  short_description

  Know before you offer. True monthly cost, price vs. Zestimate, and market signals on every Zillow, Redfin & Realtor.com listing.

  Home buying calculator for Zillow, Redfin & Realtor.com. True monthly cost, price vs. Zestimate, and negotiation signals. Free.

• May 6, 2026
  name

  HomePilot – Home Buying Co-Pilot

  HomePilot – Home Buying Co-Pilot for Zillow

Permissions & access

Permissions

storageactiveTabscriptingsidePanel

Host access

https://www.zillow.com/*, https://www.redfin.com/*, https://www.realtor.com/*, https://homepilot-production-c63a.up.railway.app/*

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