This inspection came back citing issues with the paint, the garage door, and some problems in the basement, and now I can't close until these repairs are done.

If you have documentation saying you wanted white paint, and they paint it black, it's on them, if not, who wins on he said, she said, and who doesn't have hard feelings afterward?

Paint, flooring, mechanicals, roof (?)

many of the big institutional buyers do have age limits.. and that usually is homes that were not built with lead paint at all.but in a lot of markets especially big east cost upper mid west housing stock is old you have no choice,.

A finished garage, perhaps with the wall painted, looks much different than a raw concrete monolith.

I would also get a fresh coat of paint on that wood siding and plant some nice shrubs and flowers along the entire width (under all the windows around the front of the house) and freshen up that landscaping - it is the very first thing people will see when they pull up.

I obviously need to get into the unit, probably put a coat of paint on at the least, and get it rented as soon as possible.  

I'm sure you will run into situations where you need an expert so have help on deck but demo, painting, dry wall repairs, easy stuff can be done by you!

You could save tons simply staining/sealing floors and painting.  

If you have $25K to put to use, best to use it on kitchen/bathroom remodels, landscaping, fresh paint, hardwood or similar floors instead of carpet, etc.