Do they take credit cards

Only debit cards. There's a $3 fee, but the atm inside only charges $1.60, which they will tell you right away when asked.

I can verify that the limit on debit cards does seem to be $400.

Debit cards, yes. However, they do have a limit on how much you can spend on it of about $400, if i remember correctly...

Yes

Only cash and debit, no credit.