Market square in Belmopan is where many businesses are located. This includes two banks, two computer part stores, the post office, several government buildings, the bus terminal, an office supply store, and several restaurants and food stands.
Tuesday and Friday are open days where people set up a variety of different stands to sell everything from apples to zippers. A skilled bargain hunter can find some very good deals. On open days its best to get there early so as to make sure you get the good stuff first.