Welcome to MaleSurvivor Azraphale,
I live in a motor home year round and work in campgrounds. The site rent is taken off the hours worked and usually the salary is minimum wage. My wife and I have been making it work for years. You may want to contact local campgrounds and ask if they need a mechanically inclined guy for 20-30 hours per week, and then ask about trading work for a small rental and some pay.
No one wants to be in a campground in the winter if they can drive south, so there may be some management opportunity there as well if you can stay and take care of the park for the winter.
Let me know if you need further information. Please take care of yourself in your recovery. Know that you are doing your best and it IS good enough, soon you will understand more and that will lead to a more care for yourself,