Which ecommerce platform to use?

Hi everyone,

I'm currently working on a brand new online boutique for self-made clothes. I don't have much knowledge about building web-sties, so I just need a platform with basic functionality like categories, product options, changing site design and etc.
I've came across these solutions:
Weebly - have most of I need, but looks more like a site builder, and missing some ecommerce features
Sellbeing - simple and easy to use, great design tools
Squarespace - looks a bit complicated, could find out how to do basic stuff

So is anyone have an experience with any of these platforms?
Thanks in advance