If I unemployed a user do they still have access?

In the employee section you can manage your employee's restrictions, and you can also unemployee the user. If unemployed, they will lose access to the software and not be allowed to login. So no, an unemployed user will no longer be able to access SpotsPOS under your account.

Note:
An unemployed user can re re-employed from the Shop Overview Page, accessible via the Manage Shops page in "More".