Service fees. Airbnb charges hosts a 3 percent fee that covers the cost of processing payments. HomeAway, which owns VRBO.com, charges hosts for listing their homes on the site. People planning to use the site regularly can pay $349 annually to advertise their property and are not charged a commission for each booking.
How is booking making money?
Well, Booking .com actually makes money through charging hotels for selling their inventories. And when someone finds a suitable hotel and reserves it through their site, only then Booking .com makes profit. But they don't charge their guests to make money. Instead, they take a percentage from the sellers/hotels.
What percentage does Expedia take?
For most large hotels, Expedia typically buys a block of rooms at a deep discount and resells them at its discretion. For small hotels, Expedia acts more like a travel agent, booking rooms on behalf of customers and charging hotels around 25 percent commission.