Hi,
I am developing Inventory/POS System small/medium company. I get a requirement from my new client that need my program to handle case as below:

1. My client has couple of branches around my country.

2. Once any customer come to any of his shops to purchase, e.g. purchase TV frm shop A. If the TV is out of stock in Shop A, shop A may request other shop which have TV on hand to deliver TV to customer. Assume shop B got TV

3. Deposit will be received from shop A.

4. TV will be delivered by shop B, the balance amount will be collected by shop B either.

Any ideas on how to do this?
How to handle the stock and the amount collected?
and etc

For your info, my client have web hosting.

Please advice. Thank you