Motorhome age is not going to be a problems in most of the trailer parks and RV parks used for stays of several months by people who travel and work. These are almost a different network of parks from the ones catering mostly to recreational travelers who worry about what their neighbors look like.
Winterized usually means that the RV has been prepared for winter storage by removing water from the plumbing; it does not mean an RV adapted for living in winter conditions. Unless you plan your locations to be in areas where climate is moderate at the time you are there, climate might be your second biggest problem. RVs can be difficult to heat when it is very cold, and a challenge to keep comfortable when it is very hot, particularly when it is hot and humid, or hot and sunny, or all three.
If you are going to be in very cold places, it can be difficult to find RV parks open. RVs don't hook up like mobile homes, for which heat loss from the structure helps protect utility hookups under the house. Trailers can sometimes be adapted to serve as small mobile homes by rearranging hookups to sit on a mobile home site; this is harder to do with a motorhome. RV hookups are not under the house, they are exposed to the weather.
Biggest challenge will be whether or not you and your partner can live together long term in the confined space. Thinking this through, working out living patterns when looking at RVs, can help you figure out just how much RV you need. For a lot of couples that choose to start out small, then go through a few cycles of upsizing, this personal space issue is behind that. That, combined with cabin fever.
My wife and I were together 38 years before buying a 30 foot motorhome for road tripping. We did fine in 800 sq ft apartments, 1200 sq ft homes (with two kids), long road trips in cars, even three-four week cruises in 80 sq ft cabins (but the whole ship for getting away) and thought the 200 sq ft of space would be plenty for two of us, with separate sleeping and living areas. We found that we were good for about 3-4 weeks on RV trips, before we started tripping over each other, and agreeing it was time to go home for a break from RV living. One of the issues was that she watched TV, and I do not.
Since she passed away, I've tried RVing alone, and find that the space is now too big for me, as I rattle around in it. One small room can be enough for one person.
So I guess what I'm saying, you need to try out the space. Act out who is going to be doing what, where, and when. Some people work this out just fine at 200 sq ft, others need 300-400, and still more just don't work it out at all. Someone can't go out to the barn, shop, or garage to get out of the other persons hair, no space for a den, sewing room, or man cave because all the living area is in one small space. You can't even go work in the kitchen, because the kitchen is in the living room. It all gets more difficult when you get away from being in an ideal "camping" climate, and you cannot move some of your activities out of doors.
