Integrate Custom Open Cart Product Fields - Software Development

General information for the business: We sell small form factor products to a UK audiance via an Open Cart / Open Bay solution
Description of requirements/functionality: PLEASE NOTE: This is specifically a module coding for Open Cart 2.X

We're about to embark on manually transfering our product range over to a new open cart store, and our new store will be trading under a different brand. Whilst we are manually setting up over 1000 products again, we want to add some additional admin product information that WILL NOT be visable to customers:

Vendor/Supplier: From a drop down list, seperate admin page to maintain the list;
Current Cost: Currency field;
Invoice Item Name: Text Field;

These fields can exist on the main data tab, or can be in a new tab on the product page. The data will be stored in the open cart database, and referenced by the product_id. There is NO requirement to have different costs or information for each option, nor is there any requirement to have any reporting at this stage.

Supplier list will be maintained in on a page - We currently only need a list of suppliers that we can add to.
Specific technologies required: OPENCART 2.x
Extra notes: Happy to answer any questions. May lead to further work in the future. Don't see the fixed price as an obsticle to asking for more if you can demonstrate you have done similar work before.

Do not want to receive blanket requests from people who have no experience of open cart development. To confirm you have read this and the spec, answer this question in the first line of your reply: What is 10 plus 2?