Is it even possible to have multiple businesses at the same address without breaking Google’s terms and service agreement? Yes it’s possible but you want to set it up a certain way. While it’s uncommon, there are locations that have multiple businesses at the same address. An example would be a shell gas station that has a subway and Dunkin Donuts inside.
If your business is an established entity with a unique tax id, files taxes separately, meets customers face to face, has their own unique phone number, then it’s eligible for a Google My Business listing.
If your listings are service area business listings you do want to be cautious of having the address the same. While it’s not against Google terms and services, the algorithm might still suspend you. In the current state of the world with Covid in play, listing a suspension might take a while and isn’t worth the risk.
Businesses that aren’t registered as legal distinct entities or lack unique phone numbers are ineligible to be on Google Maps. Also, listings that simply are there to promote different services such as a repairman having an appliance listing and a plumbing listing are ineligible.
Be aware that similar listings at the same location can filter each other out due to the Possum Effect.
The possum effect can cause your listing to flicker in and out of rankings in favor of very similar listings close by or even completely filter you out. The only real solution is to outrank the conflicting listing to such an extreme that Google only acknowledges your listing or move office locations.
Learn more about multiple listings here.