My store sells only digital downloads and so customer should never purchase more than 1 of the same product - but sometimes they do it by mistake and we must issue refunds - so I need to prevent it at the cart level (there are extensions for that), and also in their account. So does anyone know of an extension that can achieve this? Apparently, there used to be one (Maximum and Lifetime Maximum Quantity for Product) as discussed in this thread: viewtopic.php?f=165&t=53570 but it's no longer available?
Alternatively, can anyone offer suggestions for editing the source code (OC 22.214.171.124) so that:
If a logged in customer adds an item to cart whose model number is found in their order history (Account > Order History > Order Information) - then it throws an alert or error message?
I suspect that the file that requires a mod is catalog > controller > account > order.php around line 324.
Any guidance is appreciated.