If you enjoy the company and interaction with other artists you might enjoy being a partner. The community aspects of a co-op are as important as the cost/benefit ratio. There could be ways to maximize the usefulness of being at the store-advertise the the artist on duty and have some work in progress that folks can ask about . Pump up your sales by show adding your work on those days.
And if you get your buy-in payment back, you could try it for six months and see how it works for you.
We put together tea sets all the time. A platter, a teapot and matching cups, maybe a sugar bowl and creamer if we have them. We match the cup size to the platter, so we have lots of options depending on what products we bring to a show. If someone wants just one piece, we sell it, then assemble a different set from other pieces. If they get the whole set, they get a discount. We do this with sake jugs and cups and decanters and small drinking vessels as well.