How to Project Rental Income for Investment Properties
Projecting rental income accurately is the foundation of rental property analysis. Overestimate rent by $200/month and a deal that looks like a strong cash flow property becomes a break-even or negative cash flow investment. This guide shows you how to project rental income using comparable rentals and market data.
Step 1: Find rental comps
Rental comps are properties currently listed for rent or recently leased that are similar to your subject property. Use: Zillow Rental Manager (active listings and Zestimates), Rentometer.com (aggregated rental data by address), Craigslist and Facebook Marketplace (active listings in the area), property management company websites, and dedicated tools like Deal Run that pull ARR comps automatically.
Step 2: Filter for relevant comps
Good rental comps should be within 1 mile, same property type, similar bedroom/bathroom count (+/- 1), similar square footage (+/- 20%), similar condition (renovated vs as-is), and leased or listed within the last 6 months.
Step 3: Adjust for differences
If your property has 3 bedrooms and a comp has 4, adjust downward by $50-$150/month. Key adjustments: bedrooms ($50-$150 each), bathrooms ($25-$75 each), garage ($50-$100), updated kitchen/bath (+$50-$150), pool ($50-$100), square footage ($0.25-$0.50 per sqft difference).
Step 4: Project gross income
Take the adjusted average of your rental comps. This is your projected market rent. For multi-unit properties, project rent for each unit separately if they have different configurations.
Step 5: Apply vacancy rate
No property stays 100% occupied. Apply a vacancy rate: 5% for strong rental markets, 8% for average markets, 10-12% for weaker markets or higher-end properties with longer turnover times. Gross Effective Income = Market Rent x (1 - Vacancy Rate).
Current rent vs market rent
If the property has existing tenants, compare current rent to your market rent projection. Below-market rents represent upside potential (raise rents to market upon lease renewal). Above-market rents represent risk (tenant may leave when lease expires, next tenant may pay less).
Pro forma vs actual
Pro forma income is what the property COULD generate after renovations and at market rent. Actual income is what it generates today. For wholesale marketing to rental buyers, present both: current income and pro forma income after value-add improvements. The gap between these two numbers is the buyer's opportunity.
Related guides
- How to Analyze a Rental Property
- How to Calculate Rental Yield
- ARV vs ARR
- Rental Cash Flow Analysis
- How to Calculate DSCR