[Plugin: YAK for WordPress] Very “wordpressesc” shopping-cart

This is definitely a very simple plugin. Shure it has it’s faults and misses some details, but is aimed at simplicity. The fact that you can use posts/pages as products and don’t have to insert products and duplicate info is very nice. I guess it grasps very well the basic concepts of WordPress and is simple to use and implement. A widget to see the content of your cart is missing, but I ear the author is working on that, which is going to make it even better.
Of course, if you’re thinking of selling hundreds of products, maybe you should look into more complexe and complete solutions, like Shopp, eShop or wp eCommerce. Or a standalone shop.
The rest of us can stick with this one, I guess, and don’t have to struggle with awfull configurations (and incompatibilities with themes and plugins) of other solutions.

https://www.ads-software.com/extend/plugins/yak-for-wordpress/