After a night's stay (which includes breakfast), visitors at Casa Casa leave a gratuity of $15 to $30 to cover the cost of breakfast and linens.
"It's like saying 'We know we put you out a little bit, so take yourself out to breakfast,'" Lauren Braden says.
Evergreen and Affordable Travel Club also ask members to leave a small gratuity to thank hosts for effort and time.
Casa Casa is the new kid on the hospitality-exchange block and has 165 members in 14 countries. By contrast, Evergreen Club has more than 4,000 members, while ATC has 2,000 members.
Vetting membersAll organizations vet members the same way -- through yearly fees and member feedback. Although rare, complaints about boorish guests and uncomfortable rooms are taken seriously at each organization.
"In my personal experience, the worst feedback I've received about a member is that they arrived a few hours later than planned," Braden says.
These cheap sleeps aren't for every traveler. Those who aren't comfortable with the thought of a bed-and-breakfast stay won't enjoy a hospitality exchange. Visitors may have to share a bathroom and probably won't dry off with spa-like hotel towels.
"Sometimes a host is more chatty than their guest, or a guest is a night owl and keeps up the host," Braden says.
Club members can set expectations in the flurry of e-mails and phone calls that precede a stay, like "I'm a early riser!" or "I love my late-night 'Letterman'" Braden says.
Nancy Stein says that some people have expressed concern that they let strangers into their home, as part of the hospitality exchange.
"But they really aren't strangers," Stein says. "They're in the directory and we all have something in common. We all love to travel."
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