Seeing these makes me a bit nervous that if we buy in that market now, do a rehab, and we have to wait 4-6months to have "seasoned" tenants  before applying for the refi it may be problematic to get the appraisal we are targeting. 

Sounds like you're missing key information by saying "I don't believe I will be eligible for a traditional loan".... get that piece of data by applying for a loan at multiple lenders before assuming you can't.

The same principle will apply anywhere, but with less appreciation in, say, the Midwest, you'll be losing out on some of the sweet CA equity growth.I gotta say, choosing where to live is more than just an investment decision.

I'm going to have them sign an agreement for a non-refundable deposit of half month's rent, then apply it to the first month of rent if they end up closing.

That is to say, to re-finance a hard money loan, I would need to apply as a traditional loan? 

I might just go ahead and apply for the grant and just give it back when I purchase another property for house hacking? 

David's comment applies to our county as well.

I think you may ask how many adults and how many minors are applying to live there.

What's the best way to find and apply for these?

@Eric BilderbackNYC will fine you a cool $1M per year for not complying: https://www.npr.org/2019/04/23/716284808/new-york-city-lawmakers-pass-landmark-climate-measureOf course this only applies to buildings over 25k sq ft.