Currently I am using Travala.com but it isn’t open source and neither privacy friendly.
The only benefit is that it accepts crypto payments.
Any idea?
Doesn’t exist yet AFAIK, but there is a project trying to make it: https://openhospitality.network/
There isn’t any privacy friendly FOSS alternative AFAIK, but I use for search best prices of hotels and flights Andisearch, it’s an 100% privacy friendly AI search assistant with an own reader mode in the search results, which it permits to read the content of most webpages without the need to visit these. Also permits to view YT videos direct in the search page.
You can use it as PWA in Desktop and mobile. Best search engine ever I think, and it’s OpenSource. Only relevant results, no ads, tracking or other crap.