Hi Anna: I have stayed at the Exotic Caye Beach Resort (www.belizeisfun.com
). It is a 10 minute walk into town (if that), it has a beach bar, nice large beach area, above ground swimming pool, restaurant on site, and a new dive shop that just went in. Don and Carol, the managers, are very accommodating.
Kat, aka Tuki Tuki also rents out her 1 bedroom condo at the Exotic Caye and the price is very reasonable. Much less than what you quoted above. If you book through her, then you'll have extra money for all the fun things. You can contact Kat at email@example.com.
If you have any questions at all, please let me know. I can be reached off this message board at firstname.lastname@example.org.