I want to sell photo prints and merchandise, how easily does square space integrate?

I'm trying to decide if Squarespace is right for me. I photograph nature and want to have a simple yet clean web-site where I can sell photo prints and canvas but I want the site connected to a print fulfiller and not have to worry if I forget to process or ship a order to a customer. I see that squarespace connects to printiqe photo lab and another merchandise printer? What is the difficulty of setup and is it pretty seamless with payment and printing and shipping to the customer? If anyone has any example sites I'd love to see them. Thank you for the help.