Asstastic

I will going to Thailand on the 13th of Dec and leaving on the 14th jan which is over the 30 days visa waiver you get on a uk passport. Can I extend the visa waiver when I'm there? Or do I have to leave and come back? Or am I best to apply for a 60 day tourist visa? I think I can do that on uk passport but it will cost about $160

Im going to be working out of our Bangkok office for 3 months from the 1st Feb. can anyone recommend a website or any apartments that do short term rentals? I don't want a hotel or serviced appartment. Just a 1 bedroom place with pool and gym. Anywhere from asoke to on nut. I want to pay a maximum of 15,000 BHT a month