I once needed a bank statement for non-o extension. 1 out of 12 transfers from overseas came marked domestic, via TransferWise. I had to visit my home branch. I know from others, there are more tasks refused by some "not home branch".
what's your difficulty in understanding the word "illegal "? There exists a so called "condominium act". For renting out less than a month you need a Hotel licence. Condominiums aren't a Hotel, except of a small number of Condotels.
Residency Certificate is in Jomtien no big deal. Go there after lunch, maybe 2.00pm and you wait only 5-10 minutes. Pickup time is from 4.00pm and another 5 minutes only.