At our Co-op, we've learned to brace ourselves in advance when a certain type of client comes in. They've usually been 'referred' to us by one (or often all) of the local for-profit shops. Thanks for that.

Anyway, we try and be helpful, and we don't want to 'profile' our clientele, but we prepare ourselves for a complex and epic money-losing bike overhaul experience when clients show the following signs:

- older retired males with too much time on their hands (like me) who are constantly tinkering on their bikes.
- bikes with extensive custom mods. They know enough for attach these parts, but not the subtleties as to what is compatible with what.
- Cheap components. The few high-end bikes we see are rarely a problem. The stamped-steel parts are a misery to work on.
- Internal gear hubs or electric bikes. Especially home-cooked creations.
- lots of extraneous accessories mounted, such as ancient GPS systems, radios and speaker systems, racks and carriers etc. Generally the unnecessarily heavy the bike, the more problems you should expect.

There you go.