There’s no payment plans, no additional products to buy, and most importantly, there are no hidden costs! At this time, Tag Away can only be purchased with a credit card and all of the major credit cards are accepted (Visa, MasterCard, American Express, and Discover). It is not known whether or not the manufacturer will choose to accept checks in the future.
While there’s evidence that a “deluxe” kit exists, I wasn’t able to find it online. It’s possible that these are only available through telephone orders. Nonetheless, those seeking higher quantities of it with their order are advised to contact the official manufacturer customer service department before placing an order.