Underwrite multifamily buildings with full rent rolls
For multifamily investors analyzing apartment buildings: unit-by-unit rent rolls, mixed expenses, and investment returns across all units.
Multifamily Investment Calculator
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Create Free AccountWhat it does
The Multifamily Investment Calculator underwrite small-to-large apartment buildings by modeling unit-by-unit rent rolls, building-wide operating expenses, debt service, and long-term returns. Input unit counts, rent per unit, expense ratios, and financing terms to evaluate whether the property meets investment criteria across multiple return metrics.
Multifamily deals require more sophisticated underwriting than single-family rentals because revenue stacks across multiple units with different rent levels and turnover timing, creating complex cash flow dynamics. This calculator automates that complexity to show you whether the property is an income machine or a capital trap.
Who it's for
- Multifamily specialists evaluating small to mid-size apartment acquisitions for portfolio addition
- Syndicators underwriting larger buildings and modeling sensitivity to vacancy and rent assumptions
- Commercial lenders evaluating DSCR and property returns for multifamily financing decisions
- REIT analysts comparing multifamily assets against investment thresholds across geographies
How it works
Enter unit breakdown
Number of studios, 1BR, 2BR units and rent for each type.
Add all building expenses
Utilities, management, maintenance, insurance, taxes, reserves.
Calculate NOI and cash flow
View building-wide profit after all expenses and debt service.
Why it matters
Model mixed rent/occupancy by unit type (studios, 1BR, 2BR)
Account for non-unit income (parking, vending, laundry fees)
Test rent increases by unit type
Calculate portfolio-wide cash flow and ROI instantly
Unlock all 67 calculators + AI + reports
Full access to Multifamily Investment Calculator, 66 other calculators, live FRED rates, AI deal verdicts, conservative/base/optimistic scenario projections, printable reports, and vault storage.
Investor Starter
No credit card — ever
- 1 calculator per day (Quick Reference)
- 50 glossary definitions per day
- 5 template previews
- Market Insights (read-only)
- Limited investor games (1 game)
- +3 more features
Core Investor
7-day free trial included
- 67 Professional Calculators — Unlimited
- 1/2/5/10-Year Scenario Projections
- Save & Print Reports to Vault
- 210+ Templates & Contracts
- 110+ Phone Scripts
- +7 more features
Pro Investor
7-day free trial included
- Everything in Core Investor
- Full Investor CRM — Included
- AI Deal Analyzer & Listing Analyzer
- AI Underwriting & Property Analysis
- AI Rehab Estimator & Rent Analyzer
- +7 more features
What every calculator includes
67 Calculators
Every investment strategy — rental, flip, BRRRR, mortgage, commercial, wealth building.
Scenario Projections
Conservative, base, and optimistic 1/2/5/10-year return modeling.
AI Deal Verdict
Claude-powered analysis — strengths, risks, and actionable recommendations.
Investor Vault
Save unlimited reports. Revisit, compare, and track every deal you've analyzed.
Print-Ready Reports
Professional PDF reports to share with agents, lenders, and partners.
Address Auto-Fill
Enter a property address to pre-fill value, rent, and tax data automatically.
Live FRED Rates
Mortgage rate fields pre-populate with Federal Reserve interest rate data.
Investment-Grade Math
Every formula audited against professional underwriting standards.
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Frequently asked questions
How do I model mixed occupancy?
Enter occupancy percentage per unit type — studios might be 95%, 2BR might be 90%. Weight average occupancy by unit mix.
What's included in multi-family operations expense?
Same as single-family but add hallway maintenance, common area utilities, building insurance. Typically 30–40% of EGI.
Should I include capital reserves for common areas?
Yes — roof, parking lot, landscaping, lobby. 5–10% of rent annually for buildings 10+ units.
How do I project apartment rents long-term?
Model conservatively: 2–3% annual growth. Apartment rents track local wage growth and migration patterns, not inflation alone.
Is this calculator free to use?
Yes — create a free Investor Starter account to run 1 calculator per day. No credit card required. Upgrade to Core ($49/mo) for unlimited access to all 67 calculators.
How accurate are the results?
Results are only as accurate as your inputs. The formulas use industry-standard real estate investment math. Always verify with a licensed professional before committing capital.
Related calculators
Rental Property Calculator
Full-stack analysis of a buy-and-hold rental including income, expenses, financing, and long-term returns.
Open calculatorMultifamily Valuation Calculator
Determine apartment building value using GRM, cap rate income approach, and per-unit comparables.
Open calculatorNOI (Net Operating Income) Calculator
Calculate net operating income — gross income minus operating expenses before debt service.
Open calculatorDebt Service Coverage Ratio (DSCR) Calculator
Divide NOI by annual debt service to check whether a property meets the 1.25x lender minimum.
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