I will admit something embarrassing here: I would not have gone to the trouble of interviewing seven plumbers. And my mistake (and be honest, yours too) makes it hard for Michael to thrive and for the others to fail. After all, once you get a client, if you do the job somehow it won't hurt you much if you do it less then perfect. They might even recommend you: it's not like they know somebody else, and you _did_ do the job, after all.

This btw is one application of the Internet I expected for more then a decade and never materialized. A wiki-consumerist, with reviews in any domain. Unfortunately, I do not think it is easy.