PaymentStuff provides merchant services related to e-commerce transactions, payment processing, and security features for businesses. They offer terminals, pin pads, accessories, and supplies for retail businesses, emphasizing the importance of compliance with Visa and MasterCard regulations. PaymentStuff educates on the risks of non-compliance and the necessity of manual imprinters for retail sales. They also highlight the significance of address verification services and the benefits of special corporate cards. Additionally, PaymentStuff advises on selecting merchant services carefully to ensure formal proposals and contracts align with the original terms to avoid penalties and rate increases.