Forgive my laziness for not double checking this, but I thought I could only have either team or individual billing when I was tinkering with it.
I decided to simplify my billing method to team billing only (which has shaded my bias, so take this advice with salt)
For my user base, there would be very few situations where a user wouldn't be a part of a team, and the data they generate would need to remain accessible only to members of those teams.
Even if they were using the system as an individual, doing the same work, they'd still want to have additional user accounts (for customers and referrers), and making those people sign up on a billing plan would be difficult.
And then there is the matter of data access and sharing.
So if a staff member leaves one shop and goes to work in another shop. those 2 shops would have teams, and the user account remains in the system, but essentially dormant (and free) until it is invited to a new shop.
If the user account is orphaned because the email account for the user is no longer monitored (employer provided email) then the account could be changed to a new email. but it wouldn't make a difference because data access is restricted via team checking middleware.
If the user leaves the shop and goes to work for themselves, they may want to add co-workers in future, so having the billing based on team size fit for my system needs (my pricing is aligned directly to the team size).
And if an individual builds a business that outgrows them, they can just transfer the team (with users and data) to a new owner.