Fix anything thats broke , give it a fresh coat of paint and rent it out . 

The electrical alone will cost you $20k...Don't coat the old sewer line, just do all new...I never had a great experience with the re-coats, better to just run new ABS and be done with it.You're only allowing $125 SF for the ADU....I know it's Texas but I doubt that gets 'er done.PM me if you need more help, I just think you're a little off on your budget.

It's a 15 minute fix.1- Sticky perfect tape,2- 3 coats of mud3- touch bmuo paint 2 coats. 

I used Behr marquee and it covered everything with 1 coat just fine.

Hey @Eric Coats.

If you're working with existing cabinets, consider giving them a fresh coat of paint or refinishing them yourself to save on replacement costs.

Ned Jackson You might need 3 or more coats to fully cover.

And if you have to think about price when we're talking about $30 vs $40, then you really need to rethink your priorities (nothing personal :-)Yes Behr Marquee is up to $49 a gallon but you will never look back...you want a paint that will (usually) get one coat coverage. and will wear like iron.....

I have no time for sugar coating.

Get the local inspector(s) in there to assess the damage and let them tell you what would need to be done to pass city/county inspections and get your CO at the end of the project.