According to TheInformation, Airbnb spent about 30% of revenue on sales & marketing last year. It was up 58% in Q1 19. Would imply something like 33% of revenue this year. I remain intrigued by the narrative that they have a huge direct traffic advantage.
Here’s the link
Dramatically oversimplified but here's a comparison of Booking, Expedia, Airbnb. (Expedia includes Trivago and has COGS in other expenses so it's a mess). It appears Booking and Airbnb have ~ the same non sales & marketing expenses while Booking is 3x the revs. Is that right? 
