The Google Product Listings campaigns are included with every account with an active platform fee.

As part of the platform fee, you can create as many Product Listing campaigns as you like!

Remember, the platform fee is charged to your account if you have applicable services every 30 days.

It is important to remember that these are separate from the following campaigns;

Those campaigns require ad spend and must be purchased separately. Additional details on the billing of those types of campaigns can be found here.