What it does / Organisation
People
Adding somebody does not mean you inventing a password: the new colleague gets an e-mail and chooses their own. Every person has a function from your own list, and what they may do hangs off that function rather than off them. So the chair is called whatever you call it.
Beside that sit roles with rights per area: view, add, edit, delete and approve. Contracts, leave balance and working mode sit with the person.
What it costs
You get an environment of your own with an example company in it: colleagues, customers, projects, hours written and invoices at every stage. Nothing to set up, just look around.