I'm using Hikashop on three charity/nfp sites and it is simply the best! The non-commercial version has all the features just about any individual/small business would need. It's only if (like my sites) you need more control of company branding, international currency, etc. that you'd need to upgrade.
In 35+ years of being a computer professional, Hikashop is one of the best designed, implemented and stable bits of software I've ever used. And the support is even better than that!