Building a business of teaching music or rv repair would be really difficult while moving around. RV Parks usually have a list of rv tech's in the area that they recommend, don't think they would be willing to recommend someone that's just staying in their park. Just my opinion but I think if you need additional income you need to be more realistic. You may have to park in one spot for a couple of years, save $$$ then do some traveling. Yes, medical insurance can be really expensive. The little information I have read about the new health care exchanges give you a few options, like higher deductibles. That has been our option since we went fulltime at ages 48 & 56. We have been purchasing high deductible policies that run in 6 month increments from www.ehealthinsurance.com. If you pay the entire 6 months at time of purchase you get 20% off the premium, then we renew every 6 months. We purchase our medications from the Walmart or Target $4 list and make sure any prescription the Dr writes is a generic.