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.
You can ALWAYS be asked for proof of onward travel when entering visa exempt. It's a requirement for that entry type. Whether it's your first entry or your 10th.
It's not common to be asked by immigration, unless they are looking for a reason to cause trouble for you.
2nd entry in 12 months isn't much information. That could mean your last entry was a year ago, or 3 months ago. Those are not the same for your chances.
It's much more common for your airline to require this as part of your check-in though.