Some of them even walk off the job, even after they pull permits and are technically responsible for the work.  

If the house doesn't pass the occupancy inspection before closing, the municipality can usually issue a temporary occupancy permit.

There are pot holes at every step form entitlement to permitting to the vertical and getting CO. 

So are you trying to avoid pulling permits? 

Does it require a highway occupancy permit if its on a state road, in my area it cost me around $1000 just to get the permitting and design for my driveway entrance.

Another key change is making sure your contractor actually sticks to completion deadlines...why, because of how extremely tedious permit inspectors are getting in some cities, which can slow progress in and of itself.

Understand the local permitting requirements, keep eyes on your property to avoid squatters, and make sure you have a great vacant insurance policy while you're renovating.

For our ADU (garage conversion), I am handling the design/engineering and then selecting a final contractor once its permitted and ready to go. 

Also if this property is on septic that also can throw a wrench into the ability to call a space "a bedroom" as septic systems are sized and permitted based on the bedrooms.

Dealing with the City for permitting.