I just got back from Patong and I stayed at Patong Villa. Pretty decent hotel with a nice pool area and friendly staff. I paid 2000 bath for a bungalow room but regular rooms where available for 1100 bath. There was no joiner fee but still I made sure to get it in writing from them on one of the emails.
www.patongvilla.com if you want to see more.. Close to Bangla road and the beach.