They refuse to get their payment processor on a call with me and amex to resolve the issue. 

A thermal camera inspection would give better idea if its because of cold air getting in or the room does not have enough hvac / heat source

Provided you are sticking to the letter and spirity of your rental agreement, you have to set boundaries People that get indignant over you setting boundaries are not worth worried about. 

It's so nice to have that safety net.

 - like we ar nice, deduct portions instead of full amount..this goes to court and judge rules in our favor and that means the smaller amounts we offered being nice.

Not the nicest areas, but nice enough.. and I would be looking for minimal cashflow, banking on appreciation. 

From what Ive read, it looks like I may have to get a business certificate to do this in SF but Im not sure what that entails or what else is involved?

Yeah, no question, I'd be taking my $2.5m payout on my $2m property and going to Carolinas, they got dang nice beaches too. 

And the more there is, the more log jammed the system get's, the longer they all take. 

We were fortunate to make a nice little return and their $500 turned into $750 in a matter of 6 months.