If seller agrees to do all of the repairs before closing, how can I ensure quality?

[Diana Tran]

I'm a first time home buyer, right now under contract to buy a duplex in Tampa. After inspection, we discover there's drywood termite damage, moisture/water leaks seen from the attic and ceiling, roof doesn't have a permit with old patches. Owner agreed to fix everything. 

We are purchasing this remotely. This is our first time working with this real estate agent. We are mainly worried about the quality of the repair. How can we reduce our risk and ensure the job is done right? For those doing all of this remotely, how to ensure quality assurance when it comes to repairs?

I was told to ask about warranty, look into who's the licensed contractors, and perhaps get a real estate attorney.