Is there a way I could make a particular category in my cart set up so that if unregistered the user sees call for price, but if registered they get normal add to cart and pricing functionality?
I think you can do it with a combination of usergroup pricing and the “zero price - allow to add to cart” option. I.e. if a particular user group (0 for unregistered users) has a price of zero and then registered users have a non-zero price then the unregistered users would do what the “zero price” setting says to do.
You might have to play to see how it behaves.