A card shows a price only after we have read it from a shop that has the item in stock. A percent off is that shop's own regular price against its sale price. We do not type a number in to fill an empty card, and we do not guess what a gun "should" cost.
A firearm still ships to an FFL. A suppressor is still an NFA item. The card is the price the shop published. A transfer fee and a tax stamp are not inside that number.
Deal alerts and the Friday list store the email you submit. If a webhook is configured, the same lead is forwarded. If it is not, the lead stays on this site and no email is sent.