Dealership: Yes or No?

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Hi, I'm planning to take my 2007 Hyundai Tucson into the dealership for the first time to get an oil change. I usually take it to a mechanic friend of mine who works at a Honda dealership but he's unavailable. He usually also tells me anything that may be wrong with it or if it's in good condition. The only time my vehicle was taken to the Hyundai dealership was a few years ago when the "check engine" light came on and my father had taken it to get looked at. The dealership charged somewhere around $250 just to look at it, and "recommended" several things to help improve the vehicle (i.e. new tires, etc.) which would cost thousands. Even before my father came back with the SUV I had Googled why the "check engine" light was on and one of the possible problems was that the gas cap might not have been closed completely, which turned out to be the case, and I had closed it fully before he took it to the dealership. It also didn't seem as if the dealership even checked up on or solved that issue anyway. I'm a bit hesitant to take it into the dealership now, but the cold weather is already here and I'm close to the mileage mark for my next scheduled oil change. What should I do? Should I take a leap and take it to the dealership, or wait until my friend is available? Thanks.