In my search for an affordable ecommerce solution, I have checked out so many offerings! One offering was Shift4Shop, supposedly free. The reviews looked good, but then I checked their website. Copyright not updated in a couple of years was the first clue. Links that don't work. There was a module that looked interesting, but the link took me to Prestashop's site. I looked up the company that made the module and emailed them. I emailed Shift4Shop. Never got an answer from any of them.
I will post more solutions that don't pan out as I have time.