RV types for full timing

Another important thing to consider is the RV you plan on full-timing in designed and built for more that two seasons? All too often I read about people trying to get their RV ready for their first winter. Skirting, extra insulation, 2 or 3 more heaters, heat lamps in storage areas. I have neighbors in the park we're staying at (central AL) have freezing issues every time the temps drop to 20 or lower. Most of the reason for this problem is weekender rigs used for full-timing.