Should be 500 baht. At least it was a few years ago.
Have 500 baht ready with your passport. Don't make it obvious. Just ask for express service. Have a few extra hundred in your purse/wallet in case the price has gone up.
Yes. That's normal for many immigration offices. It's how they verify the address is actually your address. Because it will go to you by mail.
But did you ask for express processing? They usually offer that for 500 baht for next day pickup. But you'll need to be there early and can't be too many people around when you ask for it sometimes.
I wouldn't put all that work into it for a 1 year lease. They're just getting you to do all the work they don't want to do and then after a year they'll kick you out and put the rent at the 55-70k you mentioned.
Unless you can get a lopsided lease where only you can end the lease with notice at the end of each year for at least 3 years, I wouldn't consider it.
EVERY visa is 2000 baht if you get it from immigration in Thailand.
If you get it outside of Thailand from an embassy, then check the embassy for their price.
But the visa won't cost much compared to the classes. You need to find a school to see how much they charge for the classes. You cannot get an education visa without proper documentation from a school.
Most of the consulates in the US want 3 months of statements but only care what the balance is in the most recent month for the DTV. You'll need the money in an actual bank account though.
Also, forget about Thai citizenship or even permanent residence. Not going to happen.
then you're out of luck. Unless you can order a new debit card from the app or the call center, you're not going to have any option except going into the bank.