Noob question about manage clients

Hi:

How do you manage clients in the following scenarios:

1. Abuse clients (abuse of resources)
2. Fraud clients (fake details, fake credit cards, fake everything)
3. Noob clients (have no idea about how to use the service they got)
4. ask ask ask clients (always ask for support even if they don't need it)
5. Clients that know more about host than you.

Thanks.