I feel that you would be better off buying the vehicle you want for a toad and adding brackets. You should be able to get a toad on the road for about $1000 if you shop. ( Tow bar $250-300,brackets $250 Brake 500). Look at Craigs list, E Bay,
Hitch trader and forms like this. As to vehicles, if you are interested in SUV's look at most Jeeps, Saturn Vue, CRV, and Tahoe. Small cars again Saturn , Honda Accord, Chev Cavalier and more.
I guess my point is I think you would be better off looking for a good used car that is towable and going from there rather trying to find one that is tow ready, and probably cheaper.