It's going to take a few months for the score to get better and stay better; 50K is significant credit card debt, so work on a budget. 

On the one side, LL's need to get comfortable paying for value and stop chewing down reasonable fees which are necessary to make the business model perform and prioritize the property. 

I like the idea of staying local first. to expand out of state is difficult and you must have a competent and trustworthy team in place which is not easy. 

Nothing to add to the education piece but I'll definitely stay engaged with this conversation.

And then comes a point when you decide whether you want to scale up or you're comfortable with your achieved state.

@Matthew TeuschelThe "risk" with Subject To is that the owner continues to make payments.You're buying Subject To the existing mortgage staying in place.

If you're operating a short term rental that focuses on <30 day stays, you should consider a Schedule C business.The 2018 Schedule E tax forms has a box for Short Term Rentals but I'm not clear what they have in mind.

Zillow says $125 rent increase equals a move and $50 increase is a common increase for tenants who stay.

you should get your financing locked down first. you may find it next to impossible to find financing for a foreigner with those kind of down payments. and for sure heed @Ned Carey advice top of the market not the bottom look for a solid 5 to 8% return instead of 10 to 15  those are for those that live there and can stay right on top of them. 

If giving a 24 hour notice Keeps your tenants comfortable, it seems like a simple solution for healthy future relationships.