When you set up a Performance Max campaign without using a Hotel Centre account, the hotel rates that are used for your ads are Google-sourced third-party rates. Your hotel ads will display third-party rates that are sourced by Google.
You can't change the hotel rates shown with your ad. Google maintains a high price accuracy standard on the hotel booking module and automatically filters out any feeds with a low price accuracy score from being used.
Note: Our goal is to have as much coverage as possible with third-party sourced prices; however, there is no guarantee of full coverage. If you are running a Performance Max for travel goals campaign, it will still deliver positive results even without the addition of price coverage.
You can't modify the booking link URL. This is configured to the booking website of the hotel that you've selected for your Performance Max for travel goals campaign. However, you can modify tracking URL parameters at the account level by navigating to 'Campaign URL options' under 'Settings'.
Note: The advertiser remains solely responsible for their ads.