While we do support tactics that can yield star-rating "rich snippets" in the organic SERPs (such as using schema markup for reviews), Google Seller Ratings source data from specific providers and only show up in Adwords ads.

Grade.us is not a provider of review data for Seller Ratings (nor are any of our direct competitors). Google has anointed a handful of review data aggregators to provide that data, and they primarily serve e-commerce and online businesses, not local businesses: https://support.google.com/adwords/answer/2375474?hl=en

To get Seller Ratings in your Adwords campaigns, you would want to use one of the providers mentioned in the above article.