Very difficult question to answer because there are so many variables. How big is your dog, for example?
๐I'd start with how much space you feel you need for you and your dog to be comfortable for long periods on the road. The smaller units are going to be easier to drive, easier to maintain, easier to set up and tear down, and more efficient on your wallet.
Second, how many times are you going to setup and tear down? This would impact my decision. A trailer/5th wheel take more time to setup and tear down than a motorhome does. If you plan on moving every week, that could impact your decision.
At 10k miles, your on my edge for a diesel based on cost of fuel. Diesel fuel costs more, but gets better mileage. If you were driving 20-30k/yr, that would have a greater impact. Nice to have, BUT, you get more space for less money in a gas rig. Our rig has a grade brake which is very similar to an exhaust brake in terms of it's function. I believe that most Class As with Allison transmissions have this function. A diesel will typically have air suspension, gas will not. At 20-30k/yr, I'd want air ride, no question. At 10K? I'd elect to spend that money on space/comfort.
As for age...tough one. Personally, I wouldn't buy anything pre-2000, but that's mostly because of slides and other conveniences that came into the market at around that time. Our rig is coming up on 10yrs, which I still can't believe, and if I were in the market, I'd have no problem purchasing it again
๐ We bought our coach sight unseen, with preinspection right of refusal, of course, but we had look at hundreds of rigs online, and when we saw this particular floorplan, we were both sold instantly. We may never have seen this configuration by just visiting dealers.
For research, we found Ebay to be invaluable due to being able to look at 100s of floor plans, and getting a good idea on pricing at the same time. We set up searches within specific parameters, and then could look at new/relisted coaches any time we wanted to. You can save a search, and you can base the search on age, mileage, price, fuel type, etc.
One thing I frequently say is that motorhomes are like boats in that there's no such thing as the perfect one. Everything is going to be a trade-off/compromise based on your own priorities, and what makes it a bit more difficult is that you're not sure what those are, due to lack of experience.
I balance that with the fact that you don't NEED the "perfect" coach...so don't get stuck in analysis paralysis
๐ Ask questions here, figure out what your short list of "must haves" is, and then everything else becomes a bit more minor.
Jim
2005 Pace Arrow 36D
Very Understanding Wife
1 Boxer ๐
3 Maine Coon cats