What part of houston are you in? I am south in Angleton. I do my own work, and with the manuals and moderate mechanical skills most of these tasks are pretty easy and straightforward.
Any dealer is going to screw you to some extent, so the more you know, the less they can screw you.
For example, most manuals tell you how much labor is in a job, so if you know that ahead of time you can negotiate costs with the dealer/mechanic based on what he says it will take and what the manual says.