In your camper and your not retired how do you afford health insurance? What health insurance do you have? We have looked at living full time in our camper but health insurance is high.
I suspect most people do it the same way that most people do who live in houses or apartments: either it's covered by their employer (and they can work remotely or are living in their RV near where their job is), or else they are self-employed and earn enough to cover the cost of what they deem to be adequate insurance. I don't see how being in an RV alters that question one way or the other.