The best route is using licensed foundation companies and engineers to conduct work surveys to determine what needs to be done and then having that work done by licensed companies with warranties. 

More or less right in the process.But you will hire someone with a home builder license, not a GC.Also important to understand the costs.

When you apply for a rental license do they look for un-permitted work?

My concern is obtaining a construction loan without a contractor's license. 

I'm a newly licensed agent.

ALL contractors that sign up with them has to be licensed, bonded, and insured.

You’ll need all the requisite licensed professionals providing new drawings of what you intend to do.

I have lived in multiple house hacks, my second house hack I never changed drivers license to address. 

You need a license when managing properties for others.   

I've purchased a few units online and they don't require any sort of licensing.