I wouldn't hop around so much either. Perhaps Bangkok for a few days, and then two islands. You can Priceline some hotels in Phuket and Bangkok (I stayed at the Shangri La for $63 a night, including taxes and fees last month).
I'd recommend staying in Bangkok over the weekend if possible. The Jatujak Weekend market (Fri-Sun) is an incredible experience. Go early though, as it get's darn hot in there. Great crafts, clothes and so much more. You can even buy a shoulder Squirrel for $10 or so.