The new VIP/Credit Bots are up! These bots work with Trade Offers. You can get the bot to add you in-game by typing !buy or !donate and they will add/message you. The new Bots accept Pure AND Item Overpay. If you want to pay in Items or Mixed, each Item must be worth AT LEAST 6 REFINED according to backpack.tf
Simply send a trade offer to the right Bot, either VIP or Credits, and the Bot will look at the offer, calculate your purchase and send you a message telling you what you’re getting, and gives you the option to !confirm to complete the trade, or !deny and cancel the Trade Offer.