Licence confusion

I'm confused....I have a business licence for 3 users.  Does that set the limit on the number of machines I can monitor and control remotely i.e. I can only ever have three machines on my account?  Or is that the number of simultaneous logins I can have, actually controlling other machines i.e. I could have 100 remote machines, but only three users can ever be accessing those machines, because the licence is only for three users?

We are a small company with an ocassional requirement to remotely access some client machines for support reasons.  In total I suppose we have 10 remote machines that we need to access, so do I need to up my current licence to be doing this 'legally'?

Thanks in advance for any help available.

Andy