Taylors are great for soft-serve, but I have never seen a countertop one that seemed to be in good working order. Also, I doubt they (the counter models) could keep up with the volume you would need for a successful ice cream shop. I would say instead that you would want a full size unit. Used could be a good option, but you would still need to be prepared to lay out tens of thousands of dollars (I have been away from ice cream for two decades, so am far from current.)
I have a cousin who has started his own part-time ice cream business. We both grew up with soft-serve, and know it's advantages to in volume, but he is scooping ice cream now. The entry is a lot easier, and if you want a variety of flavors, you don't need a new machine for each couple.
