For those who would like to know what the BBB has against me...
Some guy received my name from a shop to have me do a mechanical damage report for him to help him get his warranty to pay his claim. I went and looked at his truck, the removed heads, the leaking water pump, the leaking (IIRC it was a cracked manifold) exhaust, and the valves that were not seating properly and were causing a loss of compression... Zoomy took a shitload of pics too.
The warranty company refused to pay the claim because their inspector said the failure was caused by carbon build up.
What I saw were valves that were not seating due to heat (his H2O pump had been seeping for some time and the exhaust was leaking), and pitting (carbon, poor fuel causing impurities to deposit...), and lean and rich mixtures because of the exhaust leak, heat, and partially clogged injectors.
I wrote his report up numerous times, but each time he said, "No, the warranty company will deny it because ______ (water pump, exhaust manifold, O2 sensor, fuel deposits, clogged injectors...) is not covered on my policy."
I finally gave up and told him I couldn't help him. I hadn't charged him a dime, but he got pissed and notified the BBB because I didn't complete the deal!
He hadn't even paid me one %#!&ing penny!
About three months later, an attorney called me and said that this guy was trying to hire her for his case and she should contact me for information. I explained the above to her, and she said she was not going to take his case.

Then I called the shop where his truck had been, and they said he came back to them with a problem not directly related to the repairs they did, but he insisted that they take care of it!
I believe they did the repair, refunded him
some money, and told him to never return.

I am not a member of the BBB because they want about $500 a year for a membership that will not bring me any more business anyway.
Talk to other small (one or two person sized) businesses about the BBB and see what they say!
I did respond to the BBB, but they wanted more and more info and hounded me for membership, so I gave up.