I've been doing all my own oil and filter changes ever since I started driving back in 1968. One time back in the 80's, when I was living in Chicago, and I was driving a Volkswagen Diesel, it was January, and about 5 degrees out, and I didn't want to crawl under my car to change oil. So I took it to a Jiffy Lube near my house. Big mistake... Huge.
He managed to get the old oil and filter out, and the new in without screwing anything up. I paid him and drove home. The first thing I checked were my tires, because he did, and I didn't trust him. Sure enough, all 4 air caps were loose, and were only screwed on about 3 turns. I'm lucky I made it home without losing all of them. I then went to check the oil.... And the dipstick was missing! I found it in that nice little recess he laid it in on top of the radiator.
Then, I noticed the oil fill cap was missing from the valve cover. I looked everywhere before I found it wedged in between a little area in the back of the trans axle, where it must have fallen off the top of the engine where he laid it. Unbelievable. If I had not checked, or had driven any distance, I would have lost everything. That was the first and LAST time I ever let anyone change my oil. I do it out here in the Spring and Fall. The weather is nice and mild. Not too hot, or too cold.