Website with Client and Employee login

Hi All,

Im looking for the Design and build of a basic website for a security company with,

CLIENT LOGIN via username and password
Once clients log in they should be able to
- Update their personal details
- View/update their jobs/services
- View Invoices
- Pay Invoice / Update Direct Debit information
- View / Send Messages.

EMPLOYEE LOGIN
Employee should be able to
- Change their personal details
- View their Job Details
- Submit Time Sheets
- Update Availability ie holidays etc with 1 months notice.
- Submit Report forms for Jobs
- View/Send messages

Just to give you an idea, we are a security company that provides most services but specialise in Residential Security Patrols.

We should be able to view and update all the details of the clients and employee. Add, change their jobs, add invoices and amounts.
Ideally it would be good to send an automated email when invoice are added, and when invoices become due/overdue, also when they change their personal details.

Basically it should bring the communication between our office, employees and clients together in an simple easy way.

I want the site to be very simple and easy to use for clients and employees.