The tenant fails to pay their last month's rent and leaves the place needing new flooring and paint.

You mean the water was so heavy that it cracked the floor joists and the entire floor and basement ceiling fell in?

The property seems to be in good shape and will requirecosmetic rehab.  5/3 house 2600 SQFTWe will need a new AC, Kitchen upgrade, bathroom upgrade, flooring, painting, andcarpet upstairs.  

By the time I arrived in the evening, everything was torn up—floors, walls, plumbing.

The bottom floor is not tall enough.  

A fresh coat of paint can do wonders along with cleaning the carpet or using something like rejuvenate on laminate floors.

The condo has some issues: a faulty breaker box, old and not well-sealed windows, and uneven floors.

ie, wind damages the roof and that lets in rain that damages sheetrock, floors, furnishings,...   

Adding paint and replacing flooring is not going to add much value in the typical case.  

Get on the ground floor and start leaning.