As someone who has owned some kind of camper for about 40 years, I've noticed a few trends. First, there are only two big RV manufacturers: Forest River and Thor. Keystone was recently bought by Thor. As for trailer frames, axles, appliances, and even furniture, the brand doesn't make much difference because the major manufacturers all use the same suppliers. Almost all rv's are built very quickly and quality control is not very good. Even such vaunted names as Airstream are not what they used to be. You can check out a lot of user reviews on RVtrader's website. It is interesting that the exact same model of any brand will get both positive and negative reviews. As for coach construction, there are a few categories. The least expensive that I'm aware of is what is sometimes called stick and tin. This type of coach has a mainly wooden superstructure covered with aluminum siding. The smooth sided trailers can also have a wooden superstructure but quite a few of them have a mainly aluminum superstructure. These cost more and are often lighter than their wooden counterparts. The more upscale units have higher priced furniture and cabinetry and more bells and whistles. I currently own a stick and tin model (Forest River Cherokee 274RK). I've had it for two years and it has been pretty much trouble free and it is comfortable for me and my wife. I've had a smooth sided trailer. It was an RVision toy hauler and it worked pretty well too, but it was not as comfortable as our more conventional rig. As for towing, I've had several different trucks. They were all gas. Yes the mileage sucks but maintenance is cheaper and generally, so is gasoline compared to diesel. Right now I have a 99 RAM 2500 8.0 V10 regular cab 2wd (98K miles on the clock). It has a 2600lb payload, and will pull 12600lbs. That allows me to haul my RZR 900 or my street legal golf cart in the bed. No need for a toy hauler. The advice about payload considerations you've read on this thread is true. It's not just you and your wife, but the kids too and all of their stuff. My wife and I are old farts, so it's just us. BTW, my advice is don't haul water unless you have to. Fill up your fresh tank when you arrive at your campground if full hookups are not available. The advice about getting a unit with black tank flush is good. If, however, you should find a rig you like and it doesn't have black tank flush, there are third party solutions available to flush the tank. In the end, its not about saving money vs staying in a hotel. It's about the experience. Do as much research as you can, talk to as many people as you can. Whatever you end up with, I hope you will enjoy it. One other piece of advice that I don't think I saw on this thread as I scanned it. If you can find a rig you like with an outdoor kitchen, I think you will find it very useful to have.
Best of luck to you.
Don Williams a.k.a. librarian