Adding a markup rate will not automatically update prices on your booking platforms. Once a markup rate is in place, that markup will be added to any future price updates.
To do this:
Click on Settings
Click on Preferences
Select Properties in the left sidebar
Input the percentage of markup rate for each booking channel. This can be a positive or negative number, or zero.
Learn more about how to change the markup rate of a specific listing within a property group in this article. Adding a markup rate for a specific listing will always override the platform-wide rate.