I have never taken a car to a mechanic, but I know how you guys must feel. The best advice that I can give is for major work, get a few different quotes. If the workshop is not familiar enough with the car or the job, then take it to someone who can quote with confidence.
Don't let extra work be carried out without your approval.
Be familiar with your states governing bodies and laws and regulations.
Liscencsed workshops must comply to standards of practice.
Modified vehicles are usually not protected by these guidelines...so be very careful.
Plan your upgrades by looking at the results of other cars with similar setups.
And talk, talk, talk, before you spend.
