I resemble that remark!
In about 1981 I reached the point where you are now. I asked for tools for Christmas (still have those and more...) and a factory service manual.
Still, there are times I have no choice. Mostly related to mounting tires and alignments. So for those jobs I do three things:
1. Make an appointment at the same shop and develop a relationship with them.
2. Stand there and watch them do the work but stay out of the way and speak ONLY if there is a problem.
3. Tip well.
If I see anything happening that I don't like I quietly let them know right away. Sometimes they take it well, sometimes not. Not my problem. It's my car, I'm paying, and (sorry) I'm right. All while being nice.
Lately I have had a string of bad ones too.
1. Had brake rotors replaced and oil changed (didn't have time) - lug nuts on so tight I broke the lug wrench trying to fix a flat a couple weeks later! They put Valvoline dino-oil in my 5.7 HEMI (Jeep Commander Overland) that I run 20-50 Extended Service Mobil 1... The stinking service record can be read by a 5th grader...
Result:
- Didn't pay for Oil Change, did it myself when I got home.
- Got replacement lug wrench for free, replacement lug nuts that got ruined trying to remove them.
- Got a set of tires mounted and balanced for free to compensate for inconvenience. (see 2)
2. Brought back to get tires mounted after the flat and they didn't balance them right. Major vibe. I have to have the tires balanced again.
Bottom line they completely failed to deliver on the convenience that I went to them to receive. The part that really hurts is the letter I wrote thanking them for going above and beyond with the tire mounting - I wrote it before I discovered the vibes...
Bottom line, learn how to do it yourself and don't think you can get all three of the following:
Edited to clarify to which car the HEMI belongs