Khmer temples on the Thai-Cambodian border have caused quite a lot of friction in recent times.
Nan Rong (นางรอง) is the gateway to the ruins.
Honey Inn: นางรอง (Nang Rong). Website: website here.
Single rooms with fans and shared bath go for 150 Baht per night. You can eat home-cooked Thai meals at the inn with the family who live there: 35 Baht for breakfast, 30 Baht for lunch, and 80 Baht for a big dinner.
Nang Rong Hotel: . Website: website here.
A little more expensive, but if that is what you want.