Multi family properties are sold on rents using such numbers as cap rates, gross rent multipliers, etc. You can do your own rent surveys in the local area to determine if your rents are high, low, etc. Find out what the expectations are in your market for prevailing cap rates, etc. and price your property accordingly. Example: In this market a saavy investor would look for a gross rent multiplier of 13 or less. Hence, you would annualize your rents - say 3 units times 1,000 each per month x 12 gives you an annual income of 36,000. A selling price of $500k would give you a GRM of 13.9.