I'll be an owner-occupied landlord with a long-term tenant next door. 

so i've been reading up and listening up as well. 

Not impossible but it would be pretty tough to get an STR property approved unless you are an owner occupant.

Dewald: Some other good zips are 63074, 63042, 63044 - great for long term rentals.There are good areas in south city left as well :-)I see more and more issues with municipalities like Berkeley, Pagedale where they want to narrow down the amount of rentals within a neighborhood and require homeowners to occupy and won't give out occupancy for rentals.Let me know if you've got any questions. 

I know this might be hard to follow but hope it makes sense!

Specifically, I'm curious about the cost and process involved.I'm considering upgrading to a 400-amp service, which I believe could be divided into two 125-amp panels, one 100-amp panel, and one 50-amp panel or some other combination.

That easy question to answer will be a really great litmus test in your due diligence toolbox.If you are evaluating a REIT, it would be wise and prudent to do your homework and select the appropriate professional to guide you.

Especially one that will be inheriting a large donation like property.

How did you find someone to oversee the set up and also be your boots on the ground as needed for emergencies once the rental is ready?

Connecting with like-minded investors locally can be a game changer!