You may yet be at a stage where you need to decide on answers to some basic questions, before getting into what to buy.
Why do I want a RV?
How do I plan to use it?
How much time and money can I afford to put into this activity?
What to get, how much to put into it, depends a lot on how you think you might use it. You may need a lot more space if you are going to live in the RV extensively, compared to either using it as a travel vehicle or a weekend cottage in the woods or at the lake.
Motorized works better if you are going to be moving more than you are sitting, but there are other reasons for choosing a motorhome, like your towing issue. However, if you are parking a motorhome in one place for a long time, then you are back to towing, only now the tow is a second motor vehicle.
As for age, I don't think there is any measure of "too old." Condition is more important than age. I know people who have found excellent RVs, motorized and towable, that were 20 to 40 years old, for a few hundred to a few thousand dollars. The are useful for the way they will be used (in most cases, a week or so at a nearby campground every month through the camping season). Cost of ownership is low because price and value are low, keeping cost of money, insurance, and licensing low.
But cost of using the RV, when traveling, is another side of the picture, because that means money for fuel, tires, drivetrain maintenance, and for that purpose a RV that is newer in the sense of "less worn out" is less likely to have a lot of surprise expenses from deferred maintenance catching up with you.
So if you are just going to run out to a nearby campground every so often, what fits your needs can be quite different than if you want a RV to live in full time and travel 50,000 miles a year. And there is a full spectrum of needs and solutions in between.
For singles and couples, more interested in camping than having a full-scale house on wheels, a camping conversion of a full-size van, or even a minivan (like the old VW campers) is an alternative. But that's camping, a different lifestyle than living in a 240 to 400 square foot house on wheels. That's the "how do you want to use it" question.