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At this point I don't think brands are important. When you look at RVs of any kind. You need to check out, are the fresh, grey and black tanks heated. Usually heat comes from the furnace into that area. Next, where are the dump valves? Cold weather RVs have the dump valves located into the heated area. Valves do freeze. When the dump valves are in the heated areas there is long extentions on the valve handles that extend out of the heated areas. If you look at RVs and you see dump valves in the open it is not a cold weather type RV. Just some thoughts. You could think about a toy hauler. Great place for dogs, plus a work area etc. Dogs in the RV while traveling is not a good idea. I'm not a 5ver fan. Been there done that, but this is about what may be best for you. Others may have many more ideas. I have found that camping in temps below 10 degrees F is questionable in any RV. JMHO from living in Wyoming and traveling in the winter times quite a bit. However, I blow out my water lines and empty tanks when the temp drops below 10 degrees F. then de-winterize when temp warms up. I just use air to blow out my lines. When it is cold I use RV anti-freeze to flush toilet etc. I don't want those dump valves to freeze. This is some very basics. As you look at RVs you will start to see more of what you need for cold weather.