One of the most important factors to getting your Google business listing ranking in the top three spots in the local maps pack (maps listings) is the amount of reviews your business listing has. Simply search your industry plus your city on Google and you’ll most likely find that the business with the most Google reviews holds a top three spot in the maps pack. You should adopt an ongoing strategy for asking customers for reviews so that you can acquire more Google reviews than your competitors. Keep in mind that they don’t have to be all 5-star reviews. The overall quantity is more important.
Google Business Profile Categories List
Here’s the full list of all 3,000+ categories for Google