Yes you pay the gas bill for the heat, but on a newly refinished four unit, that won't be terrible and the rents will more than cover it.

You might need to refinish it now and again, but, if you can do the work and have access to a sander, it is fairly quick and quite inexpensive.

Then you have to refinish it every so often which can be half the price of the initial floor investment.

l bought it for $165,000 putting in a $35,000 renovation (new roof, new kitchen,  refinish flooring, paint, several new doors, upgrade heating system) so I'll be all in at $200,000.  

My cosmetic rehabs generally include the following scope: floors, paint, new fixtures (electric/some plumbing), knobs/hinges, and cabinet refinishing+hardware. 

It also would depend on the size of the kitchen.http://www.diynetwork.com/how-to/how-to-refinish-cabinets/index.html

It's pretty comparable in price to laminate and you can refinish it 1-2 times unlike laminate.

All new paint, new 6 pannel doors throughout the house, new trim and molding, all new light fixtures, completely gutted and updated both the main and master bathrooms, new carpet, sanded and refinished the kithcen cabinets, new laminate wood flooring in the kitchen and dinning room, new stainless steel kitchen sink, new stainless steel appliances, new garage door, and a new roof in 2016.

I know what a bathroom costs me, a kitchen, refinishing hardwood floors, painting, plumbing, electric, HVAC, roof, etc.

Spend several days/weeks peeling the paper and refinishing and painting the walls ourselves OR demoing all the walls and rehanging new drywall altogether.