Fear of compliance is a myth and it's very simple when it's explained correctly.Adam Atassi 

You confirmed that some of my fears/suspicions may be valid.

Lease option was the first thing I thought as I was reading your situation, but I'm not well-versed enough in them to tell you whether there's validity to your fears or how to address them

Most of my rentals have tenants that want to move in before we can have the place ready for move-in and this is at market rent (there is no need to charge below market rent to entice renters).In San Diego I do not fear a tech downturn or exodus. 

That has been my biggest fear - that I have my unit sit vacant for a long period of time.

I believe its not an issue until its over 51% rentals. if you can prove to homeowners that there is no reason to fear becoming non warrantable, they may vote in your favor.my suggestion is get together with other landlords in your community and work together.

We fear that it will require a lot more maintenance and annual tenant changes.

Based on my research, Charlotte seemed the best bet in terms of house price to rent ratio, the age of the house ( i didn't want to invest in older houses in fear of more repair costs and such), and finally potential appreciation (though after listening to bigger pockets, I see that investors mostly care about the cash flow and buying just for appreciation can be a gamble).

@Brian Burke - I get your point about markets not tracking in parallel but part of my fear is entering an out of state market now and not being able to exit when and if the market I live in shows an opportunity and I need that capital back.

I fear that depreciation could make or break the deal.