<%= render @account.invitations %>
You will render a list of invitations. You have to render something else here. It is actually an information about remaining_invitations count. I have just added the meaning to 0 and positive integers by using a class for it.
If you reneder then it renders one of two templates.
Rendering a collection is easy as you said it is rails magic. I do it the same, but I add separate meaning for 0 and positive values.
Two possible outputs:
- you have X invitations left,
- Upgrade for more invitiations.