If you’re not dead set on house hacking specifically, I’ve got a couple of ideas that might get you started without having to prove income.

@Kevin TurciosJoin local real estate clubs, attend meetups and events, explore online networks, connect with local realtors, analyze the market, and consider finding a mentor.

The host, Mike Jake, owned up to 150 SFH's in Colorado Springs at one point and grew his business from scratch by finding off-market opportunities and implementing several creative financing strategies. 

Side note - he'd be better off if his tenants were scared off since they are paying far below market rent!

FMR in our markets is around 900-1100 monthly for such properties, so the cashflow is there.

Tenant protection issues - We’re in CA and introduction of limits on rent increases so want to be sure that we have the lease structured so the tenant reverts to a market rate rent at the end of the 3 year period or moves out if unwilling to pay that rate.I’m struggling with the 3 year lease being long, I don’t think I could enter an indefinite (til death) lease.Another thought what if one spouse dies and the survivor remarries a younger person?

There are no laws, rules or regulations preventing any foreigner, American or otherwise, to buy property in CDMX or Mexico for that matter.If, by having success, you mean getting a profitable investment, I'm sure many American and other investors got that over the last few years (I personally haven't since I've focused my efforts on Mexico's beach markets, which are far better in my opinion.

3 quality tenants in place paying just shy of fair market value. 1 vacant turnkey unit. 

Are these good markets for fix and flip transactions within my budget nowadays?

Amenities are extremely market specific.