Configurable "Add Funds" link
I have 3 packages of "prepaid support care" which are hours of support my clients can purchase in advance. I currently have these set up as products but these essentially should be treated like credits since future invoices will be deducted from it.
I wanted to send the user to the "add funds" checkout page directly, bypassing the part where the user sets the amount, I would like to include the amount in the link so all they have to do is checkout. (like when including discount codes on the url)
This way I create the sales page with the pricing tables and just link the packages to whmcs accordingly.