Rental Property ROI Analyzer
Run the numbers on any rental property in minutes instead of hours
Why people pay for this
One bad deal can cost tens of thousands. A $20 tool that catches a money-losing property before you buy it is the easiest decision an investor makes.
Target Audience
Real estate investors, landlords, property managers, real estate agents advising investor clients
Suggested Price
$49/year
Est. Build Time
2-3 days
What This Is
A financial calculator specifically built for evaluating rental property investments. Users enter purchase price, expected rent, expenses, financing terms, and vacancy assumptions — and the app calculates cash-on-cash return, cap rate, monthly cash flow, and long-term projected returns. Replaces the spreadsheet that every real estate investor maintains.
Every rental property investor runs these numbers before buying. Most use a spreadsheet they've built themselves (and many have errors in it) or a paid subscription tool. A focused, well-designed calculator that handles the standard rental property math and presents it clearly has a ready market of buyers who analyze deals regularly.
How to Make Yours Different
Focus on a specific strategy: long-term rentals, short-term/Airbnb, house hacking, BRRRR method. Each has different variables that matter
Add a "deal comparison" mode that lets investors compare 2-3 properties side by side on the same metrics
Include a "stress test" feature: what happens if vacancy goes up 10%? If interest rates rise? If rent drops? Investors love scenario analysis
Make the output shareable — investors often need to show numbers to partners, lenders, or spouses. A clean PDF summary beats a spreadsheet screenshot
The Starter Prompt
Copy this into your vibe coding tool. Customize the [bracketed sections] with your industry knowledge.
Build me a rental property ROI analyzer web app. Here's what I need: **Core Features:** - A property details form: purchase price, down payment %, closing costs, rehab/renovation budget, after-repair value (for BRRRR/flip analysis) - A financing section: loan amount (auto-calculated from purchase price minus down payment), interest rate, loan term, loan type (conventional/FHA/VA) - A rental income section: monthly rent, other income (laundry, parking, storage), annual rent increase assumption - An expenses section: property taxes (annual), insurance, HOA, maintenance reserve (% of rent), vacancy rate (% of rent), property management (% of rent), utilities (if owner-paid), other recurring expenses - A results dashboard showing: monthly cash flow, annual cash flow, cash-on-cash return, cap rate, total investment required, monthly mortgage payment (PITI), expense breakdown, gross rent multiplier - A 10-year projection table showing cash flow, equity growth, and total return year by year - An option to save and compare multiple properties **Design:** - Numbers-forward design: the results should be prominent and easy to scan - Color-coded results: green for positive cash flow, red for negative - Responsive — works on laptop, tablet, and phone - Clean, financial/professional aesthetic (not flashy) **Technical:** - Single HTML file with embedded CSS and JavaScript - All data stored in localStorage - Real-time calculation updates as inputs change - Print-friendly results view **Include these [STRATEGY]-specific features:** - Relevant assumptions and defaults for [long-term rental / Airbnb / house hacking / BRRRR]
Got the prompt? You're halfway there.
Build it, test it on a real scenario, then come back to list it.
Pricing Guidance
$49/year
Annual subscription. Market conditions and interest rates change yearly, and you can update cap rate defaults and add new analysis features.
One bad deal costs tens of thousands — your tool pays for itself protecting a single deal. Annual updates let you keep market assumptions current and add comparative analysis for new investment types.
AppGild takes a flat 20% commission. Monthly or annual subscriptions give your buyers ongoing value and give you recurring revenue, a win for everyone.
Getting Started
Pick a strategy focus you understand (or invest in yourself)
Document the exact calculations: mortgage formula, cash-on-cash return, cap rate, and 10-year projections with appreciation
Build and verify every formula against a known-correct spreadsheet or manual calculation
Analyze 3 real properties (Zillow/Redfin listings) to test that inputs and outputs make sense
Share with an investor friend and ask if anything is missing from their analysis workflow
List on AppGild targeted to your specific strategy niche
Ready to build this?
Copy the prompt, open your building tool, and start. When it's ready, list it on AppGild and start reaching buyers.