I'm assuming you have your my business profile already set up on Google?
Once you start getting reviews then they will show on the maps listing.
I send my customers a follow up email thanking them for their business, with an html link to my Google business reviews, asking them to leave a Review.
I see what you're talking about now.I do have a google business listing with 12 reviews. Maybe you need 20 plus reviews or something to get the quote under your listing. For instance Stanley has the customer review under their listing and my OverlyClean does not.