We just bought a brand new Jayco 23B for $16,900 from a dealer in Grand Rapids, MI. We have had a PUP, 29 ft Travel Trailer, and the last four years, 32 ft fifth wheel. We love the 23B. Has more countertop space than our 32 ft fifth wheel, and a slide out with jackknife sofa. Two queen tent ends, and large u shaped dinette that makes into a bed. Your kids are still little and may not mind sleeping in the same bed. Mine did when they were little (16 and 11 now) and we had a PUP. We are very happy with the amount of storage in this unit as well. This unit has a dry weight of 3900 and is 24 ft. They are asking quite a bit for a 2010. I would talk them down seeing you could get a brand new Jayco for around the same price. Heck, come to Grand Rapids for a great deal on a new one!
Jayco also has another floor plan that has three tent beds but you are giving up the u shaped dinette and for regular dinette slide out and the sofa is a bit smaller. We always liked the larger dinette so we aren't smoothed together like a normal one does.
Both floor plans have plenty of room because of the slide outs.