Buy 3 & Get 1 Free Capability

I am looking for a way to handle buy 3 & get 1 free. I found the Jigoshop Customer Discounts plugin, which looks like it supports buy 1 get 1 free, and I am wondering if that plugin has the capability to do the following:

If customers add 4 products to their shopping cart, enter a coupon code, the lowest priced item would be discounted 100% off so that it is buy 3 & get 1 free. That would be absolutely awesome! Pushing the envelope, if they add 8 products to their shopping cart, enter the coupon code, it would automatically discount the 2 lowest priced items 100% off so it is buy 6 and get 2 free.

I don’t know how big of a need other people have for this, but it is a sale we run continuously and have constant customer confusion about how to take advantage of the buy 3 & get 1 free. Right now, we tell them to buy 3 and tell us which additional 4th item they want for free in the notes section so that we don’t charge them for the 4th item, but this always confuses them and they buy 4 and get upset that their order was not automatically adjusted. Additionally, savvy customers take advantage of the buy 3 & get 1 free sale but they also enter a coupon code to receive an additional discount. If the buy 3 & get 1 free was a coupon code, then we could set it for individual use, preventing multiple discounts.

If the cost was not prohibitive, we would be willing to pay to have this feature added. Please let us know if this is possible.

Thank you!

https://www.ads-software.com/plugins/jigoshop/