"All season" model is subjective and you need to take similar precautions for the water system in cold weather.
By all season, I presume this is what you meant. Driving a big boat of a rv down to the L48 in the winter is, umm, not the best plan. Doable but why? You can get 4wd Super Cs for a lot of money. Think $150k gets you in the ball park for new or slightly used and they're rare as hens teeth.
Other reccomendation, ONLY buy your rv in AK if you're dead set on supporting the local economy. Otherwise, buy one in the L48 or southern Canada.
Fwiw, the best deals are typically fall in the colder parts of the country and the spring in snowbird areas like FL and AZ.
If I was getting an over the road, lots of traveling, lots of time in the rv type rig, I'd be looking at 10-20 year old class a diesel pushers. Around the PNW, they're plentiful and in the $50-100k range, you can get super low miles, stored indoors some like new units.
2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold