I'm looking to see whether the dbase capabilities in K2 are about to use to maintain a simple community group. Particularly I’m look to see if the “extra fields” could be used to show outstanding fees($), last payment (date), insurance paid (Y/N).
The site is a closed site as far as membership goes. Profiles would be created by site admin, once created several users would need to be able to view and edit the information. Ie treasury need to be able to update dollar values, the user need to be able to update general profile info and quilifations earnt be updated by trainers and shown on profile.

I’m comparing K2 with something like contentbuilder or the like.

Hi. K2 extra fields are just extra information for items. They have no functionality and you cannot add them in a workflow without writing custom code. The best thing you can do in such cases is download K2 and evaluate it on your own. Probably you can combine K2 with a subscriptions component to achieve what you want.