Casa e Mare has probably the best value for money in Phuket. The rooms have budget prices (400 to 600 baths) but great amenities: Western bathroom (including a separate shower and free shampoo and shower gel), satellite TV, AC, comfortable bed...
Location is good, with two beaches within walking distance (10-15 minutes) and another one quite close too.
The hotel also has an Italian restaurant (great espresso!) and sells gelatto.
We will definitely go back if we can.