[folivier]

I do my own oil and filter changes. The first time I changed the oil on both coaches I used a tub to catch the 8 gallons of oil. Then I added a Fumoto valve to make it easier. Now I just save the old jugs and use them for the next oil change. Most auto parts stores will accept used oil.
Some campgrounds will allow you to work on your coach. Not all, and even then "don't ask, don't tell". There are mobile service guys that will do oil changes and other work while at a campground. Truckstops usually have a pretty good deal on services. I had a fuel filter changed at a Petro truck stop recently. Less than $50 to change it and that included 2 spares.