Banana Beach and The Palms are both condotels and are similar in some ways. Both have pools and nice accommodations. The Palms has one and two-bedroom units, and Banana Beach has one-bedroom suites. Banana Beach is expanding, roughly doubling in size and adding another pool plus a restaurant. One difference is the location -- The Palms is at the south edge of town, whereas Banana Beach is about 1 1/2 miles south of town.
Capricorn is quite different, in that it is on North Ambergris (a sizeable hike/bike, golf cart ride or a water taxi from town) and has just three small cabins. They are fine, but less roomy and less luxe than the suites at Banana Beach and The Palms. Also, there's no pool. Capricorn's main business is its restaurant, rather than the hotel.
Belize books and publications by Lan Sluder:
Belize First Magazine (http://www.belizefirst.com
Fodor's Belize & Guatemala Guide (new 4th edition coming this summer)
Adapter Kit: Belize (the first and only comprehensive guide to living, retiring, working and investing in Belize -- a best-seller on Amazon.com)
San Pedro Cool (the first and only visitor guide to Ambergris Caye)
Belize First Guide to Mainland Belize
UpClose Central America
Belize Book of Lists