New or used, have the RV inspected by a NRVIA Inspector prior to purchase. After you have your list of everything that needs to be fixed, have the dealer fix it before you take possession. Once you take it they will be in no hurry to fix it.
The western route through San Antonio is really nice. Also, the Buckhorn lake RV resort is really nice in Kerrville. Stay there a few days and visit Kerrville and Fredericksburg.