Architechtural Question

[Bill McAlister]

Hello all,

I am really new to MySQL and PHP. A friend has recently asked me to help
him create some simple dynamic web pages on his hosted account. His host is
running MySQL and PHP on Debian Linux. Since I love learning new stuff I
agreed to lend a hand (what a difference from the world of Windows!).

Basically he wants his site to have three levels of users (with a
possibility of a few more later if the idea catches on):
1. Admins (him and me)
2. Clients (the people who pay him money)
3. Managers (people who work for the client and want to access their
basic information which is to be stored in the MySQL database).

The data structure is very simple and I have created that for the most part
(thanks phpMyAdmin!). The PHP pages don't seem to be that difficult.
Overall this environment seems to be very easy to learn and quite intuitive.
I may be hooked.

My question (yes I do have one) is architectural in nature and security
related. It is this: What is the best way to allow client and manager
access. Do I create MySQL user accounts for each of them? Do I create
separate tables for clients and managers or a single user table? Do I do
something completely different? I want Clients to be able to add new users
and inactivate old ones without administrative intervention (i.e. bugging
me) but I'm not sure how comfortable I am allowing users access to something
as critical as adding other new users. Since there is a possibility of
adding more kinds of users later, I want my solution to be extensible.

Am I being overly cautious? This is not a storefront and no money is
changing hands on the site.

This isn't my normal type of work and I feel out of my depth here. Any
insight would be appreciated,
Bill