Currently, there is no limit to the number of locations. The Google My Business app can be installed once and be used for as many locations you like. It doesn't matter how many agents you have or how many reviews you receive, we will just charge you once a month for your whole Zendesk instance.
NOTE: Adding a location in Google My Business for Zendesk only synchronizes reviews and question after the installation of the app, old reviews or questions won't be synced/imported into Zendesk. If an older review shows up, this is because a review has been edited by the reviewer.