Christian, you are on the right track , you should be able to live free in a 3-4 unit, a duplex will be a little tougher but possible with the right deal. (depending on your market)Try to avoid an over under situation if possible, unless newer with sound deadening between the units, i have owned many of these and renters always complain if they hear the tenant above or below.Separate utility metering and thermostats eliminates a lot of tenant complaints also. Be wary if the units are basement or semi basement, darn minn summer rains can get them wet and musty , then the tenants move, wiping out your game plan financially, ask me how i know, could i be from minnesota ...ya , sure ,you bettcha! The basement is a great place for a coin op laundry that will give you some weekend fun mon(ey) Also stay away from old (pre 1955 prox) buildings with plaster and lath that have baseboard (radiant) electric heat unless you see the electric bills and they are reasonable. The higher the heat bills the lower your rents will have to be to compete with newer easy to heat apartments.Also when these same old buildings have the old hot water radiators tenants will complain about being too cold or hot unless they have their own thermostat.Shop around a lot before buying... Because the bigger money tends to to go for larger units and 2 -4 units are usually in less demand you should be able to find a motivated seller with a good price , then get them to give you as many concessions as you can, so if you are getting a loan your down payment will be minimal.Last but not least get a good " LANDLORDING" book and never let the tenants know you are the owner, you will always need to be able tell them you have to check with a higher authority when they ask for "stupid things". I hope my past mistakes can benefit you. Good luck.