Clearly, the electricians didn't know what they were doing when they laid down the CAT5, but I do. (I wired the last house I owned for ethernet during a renovation and it worked great) It's too late to fix my house without gutting it, but something can be done about future homes. I see a good opportunity to start my own business, because obviously no one else is doing this.
I'm getting ready to talk to the head contractor the next time I see him, and hopefully he can tell me who to talk to to get this thing rolling. However, I'm not sure what (if any) credentials I need to start doing this professionally. I assume I need to be licensed and bonded and should start an LLC, but is there anything else? I don't think this would be designated as an electrician job, since the current carried by CAT5 is minimal compared to electrical wiring and has none of the inherent danger. If anything, I would classify this as freelance network engineering. Does anyone know what it takes to start this kind of business other than the necessary skill and experience?"