Can't always only pay 2 nights at a time. I stayed at a place in Pattaya on a couple of days down and the owner ( a Brit, not a Thai ) gave the receptionist an earful for it. Luckily I was already leaving, or I would have.
I did normally pay a week in advance on second day if I liked the place, but got caught on Thong Nai Pan Yai when the first night was peaceful and every night after was ruined by a party bar on the beach. Was refused a refund but I left anyway, even if I lost a few days payment, as couldn't sleep for the racket.