Separate POS and Online inventories?

[akramer]

I can't be the only one running into this issue but I'm not able to find an answer. 

I have used Square for POS transactions for my in-person art shows for several years; lots of customer data collected there, very valuable info, don't want to lose that. I've recently decided to start selling online as well but only occasionally -- like having two-week pop-up shops (though it may become more often if it's successful). I established a simple online presence with Square, with the intention that I can easily put select products online when I want to do that as they're already in my Square POS and all the data is there. 

The challenge is that I don't want to put ALL my items in my online store; only select items. (Basically only things I can make multiples of and fairly quickly, not the OOAK and super-exclusive items). In short, I want to have a my online store be a subset of my full Square inventory, and I want the ability to easily turn the online store on and off. I don't see how to do this. If I make items 'invisible' for the online environment, then they don't show up in my POS either for the in-person show events. 

Can anyone offer a solution to this challenge?