Question: I need a tool that can warn me about suspicious sellers on Amazon and other marketplaces.

If you're looking for a browser extension to warn you about questionable sellers on Amazon and other e-commerce sites, Fakespot is a good option. Fakespot uses machine learning engines to spot suspicious activity, warn consumers about scams, fake reviews and counterfeits on Amazon, eBay, Walmart and BestBuy. It has features for spotting fake reviews, protecting against sellers, and finding the best price, so you can make a more informed purchase. It's available as a Chrome extension, Firefox add-on and mobile app for iOS and Android, and can help you avoid scams, save time and shop with more confidence.

Another option is LegitScript, which is geared more toward assessing, mitigating and managing third-party risk. It's got a lot of meaty features, including merchant monitoring, marketplace monitoring, ad monitoring and website change detection. LegitScript's artificial intelligence technology and machine learning algorithms give businesses like e-commerce marketplaces a better idea of where they stand and how to avoid problems. If you're expanding to new markets, LegitScript can help you do so more safely.

If you're looking for a more general-purpose fraud detection tool, check out Verisoul. It automates processes to try to block fraudulent activity in a variety of areas, including payment fraud and account takeover. Verisoul assesses a variety of signals, including device risk and phone intelligence, to try to ensure people are unique and legitimate. It can make automated decisions and has different integration options, so it's good for businesses in many different fields.