Way back in the early 2000's I took a b&b seminar for how to run a b&b - it was a weekend long. (the same folks still run them) I don't recall all the terms they used but one was 'booster' ... someone who promotes your place and prompts others to come and stay ... just because they love your place.
I only had two people like that and I did reward them with an extra night free when they stayed with me for more than one night at a time. I honestly don't know how you'd track it - unless you were trying to run a promotion. I guess if loads of guests were calling or telling me they'd been referred by someone. But, as I said, it was just these two people who each sent about 5 bookings my way in summer. One man declined the freebee and then sent me a gift ...
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We've pretty much seen the same thing - only a couple of people, who come back several times/year so we know they like it, have sent friends and family to us.
The best one was a teacher who came with a group from Italy. She was going off to meet a professor of mine from college. The woman leading the group was somehow related to me. (So many connections that day!)
The professor from Italy took our brochures as a souvenir. Later that summer we had a couple show up who said that professor was showing it all around town - in Italy!
Otherwise? I can count on one hand the number of guests who have said they were referred by sometime who stayed here. And most of them? Never heard of them! Don't have their names on file anywhere!
It really depends, I think, on where you're located.
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