The checklist, per location
Basic information. Business name matches real-world signage exactly, no keyword stuffing added to the name field (this is against Google's guidelines and risks suspension). Address is accurate and, critically, consistent with every other directory listing for that location (this consistency, often called NAP for name-address-phone, is one of the stronger local ranking signals). A local phone number for that specific location, not a shared toll-free line. Hours current, including holiday and seasonal adjustments, location by location.
Category and attributes. Primary category set to the most specific accurate match, not the broadest one that technically applies. Every relevant secondary category added. Attributes (accessibility, payment methods, amenities) filled in completely, these feed directly into Google's filtering and matter more than most businesses assume.
Photos. A real, current cover photo and logo, multiple exterior angles so customers can actually find the location by sight, interior photos, and new photos added at least monthly. Stale photos (same five images from three years ago) are a visible signal of neglect to both customers and Google's ranking algorithm.
Google Posts. At minimum twice monthly, per location, each with a photo and a clear call to action. Once the basics below are right, this is the cheapest lever left and the one most consistently skipped.
Reviews. Healthy, recent review volume (activity within the last 60 days matters more than total count), a response rate at or near 100 percent, and a systematic post-service request process rather than hoping customers remember on their own. Negative reviews need a professional, specific response, not a generic apology, because prospective customers read the response as much as the review.
Products and services. Every service listed with a real description and accurate pricing where applicable, not a generic category label.
The multi-location trap, specifically
It's tempting to optimize one profile well and copy it everywhere. Don't. Photos should reflect the actual location (a generic stock interior photo at three locations when only one looks like that is an easy thing for a customer to notice and distrust). Reviews and responses need individual attention per location, a response written for a flagship location's review doesn't transfer. And NAP consistency has to be checked per location across every directory (Yelp, Apple Maps, industry-specific directories), not just on the Google profile itself, inconsistent addresses across directories quietly hurt every location's local ranking.
How to prioritize if you can't do all of this at once
Start with NAP consistency and category accuracy. These are foundational, and nothing else performs well while they're wrong. Then reviews and response rate, because this is both a ranking signal and the thing a prospective customer actually reads before calling. Posts and fresh photos come last in sequence, not last in value. They are the highest-leverage items once the foundations are right, and worth very little while the foundations are wrong.