Itemized breakdown of estimated opportunity amount

Hi,

Is it possible to create an itemized breakdown of estimated opportunity amount?

We're using CRM to track opportunities and want to have an itemized estimated opportunity amount broken down by brand and product. Each brand has multiple products available, but not everything. We want sales to write in what they think the estimated $ opportunity amount for each product is prior to requesting a quote from AX.

I was looking at the OOB product entity, but it's too specific for our needs, we don't need product ID's or set price per units. I want the write-in $ amount, but limit the selections available for brand and product.  

What's the best method to record brand and product type, with an itemized estimated opportunity amount?

I'm thinking of a layout like this example:

I need to be able to graph the results to view total estimated revenue amount by brand and product type. So I can report est. revenue for Brand A, B, or C etc. or estimated revenue by product X, Y, or Z. 

Thanks