Mostly, Everything is Negotiable (Part 1)

Incident 1:
I was in a garage on Saturday to get an oil change for my car. I left my car in the garage and then went to the gym since the waiting time for the oil change was about an hour. When I came back, the manager said they found out the light bulb next to the license plate was broken and it needed to be fixed. And then he said it cost 11 dollars to replace it.

So I started my unconscious negotiating process (First of all, I didn't know there's a light bulb exist in that part of my car. And secondly, I thought he was talking about the nuts and bolts for the license plate), I started to ask them why it costs so much to replace it. I commented it only cost less than a few dollars if I do it myself. (Actually I am quite clueless about the mechanics of a car.)

Then the manager said, "OK, we can replace it for 9 dollars." Hm, just because I started asking for a lower price, I received a 18% discount, that's pretty good. Though I could counter-offer them 5 dollars and see what he would say, I didn't do it because I was surprised that the price could be lowered. (But definitely I'll make an counter-offer for my next negotiating event though.) I didn't do the research on the market price of changing a license plate light bulb on a car, but I thought it probably takes too much time for me to research on it, or even go to an auto shop to get the light bulb and do it myself. In the end, I paid 9 dollars to fix the problem.