Pumped to extend my Thai visa and see Burma, my boyfriend and I drove around town looking for a guesthouse in Mae Sai. There was little to be found. We eventually found this place RIGHT by the border. At 250 baht/night for a double room it's not expensive but boy is it terrifying. Old carpet, narrow bed, creepy halls, sketchy bathroom. The common room has some leather couches and wi-fi. The only other people we saw was a withered guy who kept staring at us or watching the BBC on top volume plus two ladies in matching tube dresses and heels who may or may not have been using the hotel as a "party" base.
This place is fine for one night but take it from me -- extend your visa in the morning or afternoon, check out the food stalls that line the road that lead to the border crossing, see the hilltop temple and then get out! Otherwise you will end up staying in a place like this hotel. Don't do it! Go to Mae Salong instead.