Well, there are folks who call AAA to get a tire changed - they need to stay away from regs. I have always enjoyed (and been fairly successful) tackling mechanical tasks so regs were just a natural when the professionals repeatedly disappointed me.
With a few exceptions, errors when you service a reg are not dangerous as they render the reg obviously unusable. The main exception is over or under tightening a connection. Follow torque specs and perform hand checks on all accessible connections.
The price your shop charged for 4 regulator kits and a BCD was not at all unreasonable. Yet, that is a lot of $$ for what was likely unnecessary service. The really nice thing about DIY is that you know your tech is every bit as concerned as you are with doing a quality job.
You make a great point about AAA, awap! I am a mechanically inclined individual so I don't look at it as a daunting task. I actaully view it as a great opportunity to purchase some new tools
So you think that the price wasn't that bad? I guess what irks me is the astronomical charges for "rebuild kits" which amounts to a bag of O-rings. They are all pretty generic in specification and $50 a kit is waaaaaay overpriced.
Thanks for all the input guys! I am going to start building a toolkit for servicing my regs.