I also do it myself. It not difficult and there are literally hundreds of videos out on the web that explain in detail how to do it. To me it's more of a hassle to make an appointment, hitch up the trailer and drive it over the RV shop, wait until it's finished, then trailer it home, back it into the driveway and into its parking spot in the yard. I live on Long Island and there aren't that many places to get type of work done, so getting an appointment isn't always easy. I usually grease the bearings once in the spring. I usually wait until there's a nice sunny day to do it. It also gives me an opportunity to inspect the brakes and make sure everything is in good working order. I guess if we towed it over 10,000 miles in a year, I'd probably do it again.