Wikipedia
ResellerRatings
ResellerRatings is an online ratings site where consumers submit ratings and reviews of online retailers, and online retailers participate to respond to reviewers and/or to gather reviews from their customers post-purchase. As of February 20, 2016, the site claimed 5,466,005 user-submitted reviews for 198,045 stores. Consumers use ResellerRatings to check the reputation of online stores before buying.
ResellerRatings operates a :freemium business model. Merchants can participate to receive certain features for free, and can subscribe for additional features.