Interspire Shopping Cart Mod: Many-To-Many Brand like relationships for Products (Product Compatibility Matrix)

I require modifications to the Interspire Shopping Cart (verison 6.0.14) to allow for relationships between Products, and another list of items. Basically, the online store sells consumables and parts for IT equipment. So each consumable may be related to one or more pieces of equipment. ie. A printer cartridge may be suitable for multiple printers, and a printer may also be able to take different cartridges. ## Deliverables **I am a developer myself so I understand what needs to be done to achieve what I'm after, however I do not have experience in the Interspire Shopping Cart. I know it will be a fairly straight forward mod, but would rather someone who has had experience do the build work for me rather than me try to learn new cart software in short time frames. **Item Types** * I require something similar to the Interspire Shopping Cart "Brands" where "Items" can sit. For example the Brand may be "Canon" and the Item would be "Printer 1". The Item must have a relation to the brand. **Item Mapping** * Existing Products in the store (which are the consumables) must relate to an "Item" above. I would like a list of Items down the left hand side (for example - Printer models), and then have some sort of mapping. I'll leave this up to the developer but some sort of drop down? * Each Item maps to one or more Product, and each Product may relate to one or more Items. Requirements** * The admin area must contain an interface for maintaining "Products" * Each product viewed from the client interface in the Interspire shopping cart must show the compatible products. * A search form must be at the top of the home page where users can select their Item to show all relevant Products for that item. I can show example sites upon request that contain similar functionality.