I am working on e commerce site these days. Every goes well but now i am stuck on discount functionality.
My client wants to have following functionality in the site
1)- i want to offer simple discounts: 10% off, 20% off with voucher or code number
2)- i want to offer discounts for multiple purchases: buy 1 get 50% off next purchase, buy 2 get 1 free
3)- recommend a friend and get a discount
Can any one shares his/her views regarding how these can work with the shop?