I did a couple of years of living out of a car (using a tent). I had a lot of prior camping experience (hiking and cycletouring) and like sleeping on the ground. I was camped exclusively in the bush or countryside except when the car required work.
There's a different set of advantages, challenges and constraints depending on whether you're living in built up areas or remote ones. I was doing the latter and have no first-hand experience of the former. In either case you'll need to think about coping with the temperature range, and food storage and cooking. Remote living presents the financial challenge of how much driving you do (vehicle maintenance + fuel was one third of my budget), especially if you need to access treatment (which constrained how remotely I could travel). Remote living can be logistically smpler in some respects, since stealth isn't an issue, e.g. I used portable solar panels to power a portable fridge and laptop and could stay in the same spot for 7-10 days at a time. Challenges of remote living can include disturbance from other campers (most commonly generators and barking dogs), having to relocate in response to the weather forecast, maintaining communications access, not always knowing where you're going to sleep that night (and finding that where you'd planned to sleep isn't suitable), and finding your way around unfamiliar places and businesses (e.g. supermarkets and mechanics).
It was beneficial for my health to do it but eventually I got tired of the constant setting and packing up, and being disturbed by the wind and by birds (many of which are
pretty raucous in this part of the world). Being able to escape disturbance from other humans was great though, and the travel helped me decide where to settle once I got tired of it.