Whenever I need to hire someone to come do work, I ask for referrals from friends and neighbors. I tell the person who answers the phone/schedules the appointment about the referral when I make the call. I also tell the worker that so-and-so recommended them. That way, if they have half a brain, they realize that my friend so-and-so will probably hear about the job they did.
Their reputation is going to be out there for me, my friend, and anyone either of us talk to.
Word of mouth advertising is worth gold if it's good. Very hard to get rid of if it's not.