Originally Posted by
FBinNY
Most better shops teach bicycle maintenance. They don't fear losing repair work because here's usually plenty anyway, but also because folks who are going to do their own work, are going to do so anyway. So they might as well teach and build customer loyalty that way.
You'll likely buy the parts from the bike shop and then when you screw up the job take it to them to fix. For every 5 customers who do it right, there's probably one guy who either doesn't have time or is mechanically hopeless.