To be added to reworked BDC Rates article: https://www.ownerrez.com/support/articles/bookingcom-api-rates-settings#in-bcom
Booking.com requires surcharges to be configured on their site. This can cause configuration issues within OwnerRez, especially with commission rates and expenses.
Any Booking.com surcharges should have a matched-name surcharge configured within OwnerRez Surcharge pages so they can be linked together when the booking comes in.
On Booking.com's side, this is configured as the "Type of fee" dropdown, this should match the surcharge Description inside of OwnerRez:
If the fee is different on Booking.com than your "standard" fee for other channels (for example a $175 cleaning fee instead of $150), set your normal fee to exclude Booking.com as a channel, and set a new $175 Cleaning Fee surcharge that only applies to Booking.com.