The nice thing about a motor home is that you can access the amenities while going down the road. This is fantastic, especially with kids that have to go pee every 15 minutes. You can have someone grab you a drink or a snack, and passengers can get up and move around from time to time making for a more comfortable travel experience.
The downside to a MH is that if you want a travel vehicle when you get to where you are going you will have to tow one behind you.
The nice thing about a trailer is that you have a travel vehicle wherever you go. But you and all your passengers are traveling in a truck, and if you need your amenities you have to pull over.
I have three big pieces of advice for anyone buying a used RV:
#1) Trust your nose! If you get in the RV and it smells like mildew or rot, walk away!. Water leaks are the death of RVs. And when you are smelling mold or mildew, you are almost guaranteed to have water damage somewhere, plus a leak that needs fixing. I have to take a daily allergy pill every time we use our RV because the mold in our RV sets off my allergies terribly.
#2) Check every single appliance to make sure it works. From water faucets to fridge to stove to generator. With water in the storage tank, turn on the water pump. Make sure it pressurizes the system and then shuts off. If it won't shut off, you've got a leak in your water lines! And if possible, let the appliance run for 10 minutes or so to make sure it's going to keep running. The generator on our RV ran when we checked it out, but it turned out it would shut down after about 20 minutes. That was $500 to fix. And if you find something that doesn't work, get an estimate on how much it will cost to fix. The broken cab air in our RV cost about $800 to fix.
#3) Google and learn how to interpret the date codes on tires. RV tires almost never expire due to tread wear, so you can't look at the tires and go, "Oh, the tires look good!". Tires have a life of about 5-6 years. They will age expire before the tread wears off. If the used RV you are buying has old tires, you'll need to factor in the cost of new ones. Our used RV had 10-year-old rear dual tires, 4-year-old front tires, and a 19-year-old spare. All were replaced to the tune of $1000.
Steve