It got popular in the nineties; on new construction, everyone had a "work done by" sign, I never believed in it and the business never suffered.If I had a company do work at my house and they put a sign up.. I would ask them to take it down. Nothing personal, it's just my house!
I was "interviewed" by a would-be client; he said a neighbor of his said I was expensive, I said "so". He said, " I want you to do the system because the neighbor said, that even though the system was expensive, you took such good care of the operation and service after the installation, that's what I want". Guess what, we did the install, serviced it, and sold it to Russ. That system was twenty years ago.Learning to get your customers to talk about you is advertising job 1.