I am a part time dweller in a Honda CRV. I did remove the 2 back seats since they refused to fold flat. The seats are in storage at a family's house so they are there when the time comes to put them back in.
I made a single bed out of 3 pieces of plywood and 2x4s. I made it so each end of the plywood would hinge so I could get to the underneath storage. And you need as much storage as possible. By building a bed platform, you don't lose that 'under-the-bed' storage.
I have that cardboard 'template' for the refrigerator. I needed to make sure the important things would fit.
I use a 500w lithium battery that can be charged via car/solar/electric outlet. I have a 100w solar panel that folds into thirds. I can charge my battery while driving or via solar or plugged in. So far my fridge lasts more than 10 hours on just the battery alone. (10 hours has been the longest I've need to run my fridge)
I also have a one burner butane stove and a notebook grill for cooking. I carry a chair, table, reliance toilet, privacy tent, craft boxes (I paint and sew) and clothes/personal needs. I am still thinking of rigging up a shower with one of those weed sprayers, and getting a solar oven.
I have special screens on both the rear windows. They protect me from dust and that means a lot, but I can put the windows down for fresh air and still be bug proof. I have a moonroof that I need to make a screen for and maybe the passenger side window. Oh, I also have rain guards on all windows except one - it flew off the other day. I am gonna contact weathertech to see if it can be replaced.
I use my CRV as a tent, meaning I don't live in the CRV, I live outside the vehicle as much as I can. I am thinking of some sort of screened-in something, but haven't found anything that strikes my fancy yet.
I read tons of forums and watched youtube, and they all talked about stealth. I am in the camp that I just want my privacy when I am inside my vehicle and I don't care if I am stealth. I live in Arizona and there is so much BLM land that you there is always a place to camp. Even if I must park at a walmart, I don't worry about stealth.
I am learning as I go just like a few people out there. I want to try this lifestyle to see if it fits me. If it works, then I will want a van.