We hired a company to steam clean the tile/grout floors and it was worth every penny.

Remember, everything is negotiable in a sale so "not paying closing costs" can be part of any of your counter offers and would have nothing to do with it being a FSBO or not.There has been a lot of good advice already in this thread, and I agree with @David Faulkner, if you're asking these questions you should probably get an agent.If you get a good agent working for you, it is worth every penny you pay them.  

Agents and property managers make pennies on rental fees.

The repairs that I could see from the walk through were minimal, carpet - I'm considering removing the carpet in all the units and getting the wood floors sanded and refinished, paint, tenting the place to get rid of pests, replacing the cabinets in two of the units - the rest need re-staining (or a fresh coat of paint),  some outlet covers, light fixtures, things like that. 

. #4 Can a seal coat get you through the winter?

It doesn't matter if they are in school or licensed  professional it doesn't matter if they wear a white coat or green coat or purple coat I am always going to get three bids/quotes.

I've seen and heard it time and time again regarding some neighborhoods that if a house sits vacant very long, copper, fixtures, air conditioners, wiring, and I've even seen toilets come up missing!  

As a wise man once told me, "a coat of paint will hide a great deals of sins."

We always put a fresh coat of paint on every apartment we rent when the previous tenant has been in the unit more than 1 year.

They are worth every penny.