GENERAL ADVICE WHEN BECOMING A LANDLORD:
Becoming a landlord should not be something one undertakes without serious consideration and evaluation. Each apartment will have to meet local codes for multi-family dwellings. These codes vary from municipality to municipality. Check with your town’s building department to find out all about the local codes that must be met prior to the issuance of a certificate of occupancy for the building you are considering.
Things as simple as smoke detector placement and as costly as asbestos, lead-based paint or mold removal must be considered prior to your purchase or your dream investment could turn into the money pit.
Because of possible tenant liability claims against a landlord, and for the safety of the tenants, I recommend all pre-existing safety related conditions, be upgraded as soon as possible. Items such as each apartment having a second means of egress, independent and adequate heat source, sufficient hot water, no roof leaks, basement access to the utilities, GFCI protection in the kitchens and bathrooms, smoke and carbon monoxide detectors, staircase, handrail and guard railing problems, wiring hazards and anything that may cause a slip, trip or fall should all be top priority to avoid trouble.
Once the units are brought up to present safety standards, I recommend an annual safety inspection to assure a continuing safe living environment for the tenants. Make sure that each means of egress is kept clear, safe and functional. Define what areas of the home are for each tenant use, and specify parking spaces. Tenants should not be relied upon to maintain smoke detector batteries, proper function of GFCI devices, etc.
You should consult the local board of health and become familiar with regulations governing "minimum standards for human habitation". Every effort should be made to comply with the standards. Lastly, I urge that you have the home inspected for lead paint, asbestos, radon or any other environmental or health related material which may pose a health risk to the tenants and a liability for you.