Create a web based sales point

I have a small business, and I already have an exist sales point software. I want a new sales point to be online and offline software. Currently I have around 300 item. The software should be able to do the following: 1. I can adjust the menu list. 2. The item selection should be based on the item name and its picture. 3. I can add the warehouse storage items and the application make the required calculation, such as the remaining items, the sales and all accountant reports. 4. The employee can use this system to sell the products only and I am only the one who can view the reports. 5. I can Issue the reports as I need, and if it is not possible, I need at least to issue 6-10 reports. 6. the bill should look the same as the current bill. 7. Currently I need it for one shop, But If I open another shop it as the ability to connect the database with any other branch... 8. It issue the accountant reports, which means, it calculate the storage items, It do the inventory, it gives me the profit, it calculate the every things needed for the accountants. Note: I am new in the business, so this list may become more or less depend on the negotiation.