Page for selling multiple buy 3 for…

Hi there. Don’t know where else to put this. I have a site where I want to offer multiple items for a discount price. I have a regular price for each item but I want to offer any 3 items for a discount price.

I envision that I have a button on each product page that qualifies for the discount, so that when they click on that button, “Buy any 3 for…”, it will take them to a page that presents a list of all items qualified. So they can select them by quantity, ( for instance they may want two of one and one of another, or just 3 of one ), but once the total reaches three they can’t add more unless they choose to buy six.

I have no idea how to accomplish this and am wondering if anyone has come across a solution or knows any ideas about how to do this.

TIA