Protect yourself: Have them show you each needed item before and after repair; get written estimate; get second opinion before; verify repairs after; get old parts.
Protect yourself: Select a shop, which is accredited by AAA, ASE and ASA. Also make sure your tech is ASE certified in the specialty he's working in. Just because a tech is certified in one specialty, doesn't mean in all areas. Test their recommendations with a second opinion.
If it sounds too good to be true, it probably is!
Have an honest shop give you a correct estimate or get ready to open your wallet much wider than you thought!