I think they're big in the border run game. Either that or safe entry fast track at the airports. I forget which one. But I've heard of them and they are legit.
I'm not sure what you're asking. Retirement visa requires proof of 800,000 baht and marriage to Thai visa requires 400,000 baht. What's your specific question?
There's no such thing as a 1 month education extension. You either qualify for a 90 day education extension or you change extension types. But if you've already maximized your education extensions then you'll need to leave Thailand.