Buy 2, Get 1 free

[Guest]

I will be selling photographic prints. I would like to be able to configure things so that if a person buys 2 prints (size 13" x 19"), they get 1 free 8" x 10" print. Is there a way to configure the shopping cart so that it can see when the conditions have been met to receive a free print (2 prints ordered 13" x 19")? So when the image for the 8 x 10 print is chosen, the price in the shopping cart is $0.00 for that print?

 

I would NOT want the condition to be met if 2 prints of any other size are ordered. (example: if the customer orders one 8x10 and one 13x19 print - the conditions for the free 8x10 have not been met).

 

Thanks,

Kerry