Create an custom extension for a Rewards Program in OpenCart

We need a programmer to create a custom extension that allows customers in our webpage to accumulate points (equivalent to money) after registering to the rewards program and use them to purchase online and also in our physical stores, this rewards program should have the customer information related with purchases amounts and accumulated points in a data base which will be accesible from Admin side (we should been able to edit and add or discount points in case customer comes to our store) and also automatically do this (add and substaract points) for purchases online using their Rewards program Number. We will create Reward cards with this number and a bar code we can scan in shops so we can acces their rewards account. This data base will make the rewards account of every customer updated in real time no matter if the customer shops online and/or in physical stores. Our webpage runs in OpenCart. Some products will accumulate some % of points and some others other % of points. We need to be able to edit this after the extension is made so we can change this % when ever we need so we can create promotions, etc.