Unfortunately, our 2003 Coleman-Mach A/C unit has bit the dust. Need to replace, and hoping for some insight... First...any recommendations on brand? Main ones seem to be Carrier, Coleman-Mach and Dometic. Second...what size? 13,500 or 15,000 btu? We live near Augusta GA and camp primarily at the lake here. And will heat strips adequately heat the PUP in the winter? We're not snow campers, so really only early fall and late spring. Third...any recommendations on companies? AdventureRV maybe??? Last...is this an easy replace/install job? Hubby is pretty handy, budget is tight, so going to do it ourselves (and by "ourselves" I really mean HE is going to do it Info on our PUP: 2003 Coleman Santa Fe with fiberglass (not ABS) roof. A/C unit already installed, just need to replace with new one. Thanks so much!!!