Here are a few counter intuitive rules, or laws, that seem to be in effect when it comes to RVs.
1. RVs are made almost entirely of stuff that will degrade if left outside for any length of time.
Your car isn't. But your camper is. Go figure. All these years those vent covers are STILL made of stuff that will dry rot in hot sun in 2years or less. And let's not even talk about decals or lap sealant...
2. RVs are designed by people who have never spent a week in one.
This explains why the cabinet that has the water filter canister is screwed shut and the LED in the light switches keeps you awake at night. And why there is a grey tank outlet under your slide out room. And so on.
3. Cars and trucks come with manuals. RVs do not.
Sure, you usually get one for the furnace, the fridge, the AC, etc. But you are NOT going to get a manual for the complete unit that might suggest best practice for use and maintenance of the camper. Imagine your car coming with only a manual for the transmission and the alternator.
4. The final assembly point for any RV is the owners backyard.
The first thing I had to do to mine was plug up all the drafty leaks and holes so that the AC (or the furnace) could actually handle the load without running all the time. A whole can of Great Stuff. And some foam board. Duct tape. You know...
5. If you don't like to tinker and have no basic knowledge of how to use simple tools, do not get an RV. See above rules.
And there are many more...Feel free to add your own.