As with hard money lenders, interview your contractor. Make sure they have done this before. Get references, check out their current projects, and ask the owners if they would recommend. You must have someone who can finish in time, on budget with quality. This is a tall order as most contractors possess 2 of these qualities but not all three. 

Manage your fix up. You must visit on a regular basis to ensure the work is getting done and getting done properly. If you wait until the end to visit you may cost your self money by having to redo items which could have been caught. 

It is important to ask for opinions on how to fix. It’s ok if you don't have all the answers. Ask friends, family, real estate agents, other investors, workers, etc. The garage was converted to living space, should you convert back? Should you redo the bathroom or will it sell well without? All have a logical solution. What is the least amount of money you have to put in to sell the quickest for the most amount?