I need a simple script to manage users, manage ip & permissions.
The purpose of this script is for user to buy credits and use an http post service on my server.  
When user makes a request via http post to my server, my server will immediately do an http post to another server 
and then my server will relay the result back to the user.  The user does not know I get the info from another source.
The script would log the usage/result of each http post. 

1. A user will http post to my URL like
www.yyy.com/../uslookup.php?user=john&pwd=23432&msisdn=12125551234

After my server receives this, my server will allow access from only approved IP's. My Server then extracts the
parameters and post to another server at
http://lookup.xxxx.com/USLookup?user=myusername&pass=mypassword&msisdn=12125551234

the xxxx server will respond with info like
TMOBILEUS or
UNKNOWN or
FAILURE

we will relay the same info back to the user. Then script logs every usage for each user.  We also add an extra response:
OUT OF CREDITS. PLS BUY MORE

2. User can register an account, click on email confirmation link. They log in and can edit contact info, and buy credits via paypal. 
If usage credit is about to run out, they get reminder email to buy more. If run out, they are blocked. 
User can see a history report on the credits they bought via paypal.
In user login, add a field for user to enter a phone number and see results of the http post. (credits are decremented).  Credits expire in X months if unused.

3. Stats: User searches and sees only their usage report as follows:

4. Admin logs in and can 
a. edit/add user credits, user ip (this is already mostly done in the script)
b. add the xxxx link, adminuser, password, etc
c. view stats reports 
d. Search and edit/view payment reports