nopCommerce

nopCommerce offers some pretty innovative solutions for the shopping cart software industry, and I honestly love the fact that it's open source, making it flexible and affordable (it's free of charge, obviously) at the same time! The platform does a pretty good job at maintaining any network of shops, and I really think nopCommerce is good!

Unfortunately, nopCommerce does not look like the most stable platform you'll ever get to use, because even though you get to program and code everything by yourself without having to stick with their strictly built templates, bugs are relatively frequent. It's true, but I guess that's what you get with any open source platform, not just this one. There are updates, but they're not as frequent.

Summing it up, I really think nopCommerce has almost everything you would need in a good shopping cart software as part of your shopping website. Once again, I'd like to highlight that nopCommerce does not cost anything, and its user interface is good. There's a demo webpage available on their website, and I suggest checking it out!