Wow fucking #couchsurfing put up a paywall so you can’t even see any of your past messages or friends without a subscription of 2$ a month, federated couch surfing when?!
Bolting it on to the existing Fediverse could work as there is already a global community here who are generally friendly, well behaved, diverse in age, ethnicity, gender/sexuality etc and even with folk being privacy aware they share just enough to ascertain whether they would be trustworthy (all the other services risk creating power imbalances, especially when relative strangers are desperate to find accomodation at short notice)