This.

I work with this one guy, endlessly upgrading what was a rather plain Jane Felt Cafe 7. He came in our shop looking for upgrades after another shop turned him away, much like the one in the OP. We were happy to do the work, happy to turn the bike into what he wanted, and started offering him a substantial discount on parts because of the amount of business he was doing with us.

The other day, I stopped by the shop for some parts, and there was a guy with a bike purchased at another shop, his son's bike that needed some basic adjustments and a new brake cable noodle. He expected to drop it off, but I did the work on the spot while he waited. Not a regular occurrence, but he was thrilled to get the bike back in ten minutes instead of the next day or two.

If the OP stopped in, same thing as above -- work with them, if we don't have what they want, see what we can order, go over different quality options, see if they are interested in any change in stem rise/reach. And hopefully provide the proper length spoke from existing stock.

We can't compete on internet pricing, but hopefully make up for it in quality of work, depth off knowledge, and friendly customer service.