I've only known one person who went to Car Toys (in Tacoma). They charged him nearly $1000 for a custom fiberglass sub box, a single mediocre 10" sub and amp (I don't recall the brand). Since then I've always avoided them.

Darn right you should be upset. You told them how you wanted your camera mounted and they screwed it up. You get a jolt every time you touch the ignition. That's not normal! They should fix it, at their own expense, and smile while doing it. Don't let them forget how rare and well maintained your vehicle is.