An oil change is cheaper that an early engine failure. A good shop will want to help you. If they educate you now it makes it easier for later. Ask for the parts to be returned before the job is started. Then asked them to show you what was bad.
Auto repair is a frightening area.
I was recently out of town and had to do the same research. I started with the local mini mart for a good tow truck driver. He then towed me to a good shop, that didn't specialize in my Mazda. I knew the labor guide hours and the parts prices. He was right on track.