yep! I have a husband/wife team I met at Jon Dons Strategies seminar a few years back. Also met another cleaner in a town just north of here at the same seminar. I get a lot of overflow near the holiday season where customers call at the last minute and I'm booked out 3-4 weeks. So I actually have two I refer work to and they both are great! BUT, always followup a month later to see if they are satisfied. It reinforces your future referrals.
Awhile back I did refer work to an IICRC Master Cleaner and was also a Certified Inspector. Thought that if he had those designations that he would do good work. Problem was that on followup calls, people complained about his workmanship. Go figure.