With your helpcenter.io account, you can manage as many help centers as you need. However, our pricing is per help center so you would have to pay the price of the subscription that you've chosen for every help center you create with us even though you will be able to manage all of them from the same place.
After you sign in, you will be presented with a list of all your help centers so you can easily manage any of them or create a new one, if you need more.