Maybe I have a different opinion about inventory, but tracking inventory as to the number of kits from a particular vendor gets to be difficult.
Let's look at just chrome sierras for example.
You can buy the basic chrome sierra from probably 10 different vendors under the description "chrome Sierra". Them Woodcraft sells the same kit as another name with other vendors using their own name. Then, you get into the variants such as Gatsby, etc.
Way too many options to track kits bought from a particular vendor.
Then you have the idea of cost. Tracking 5 kits in inventory at $8.00 each and then another 4 in inventory at $8.25 each because you bought them at different times adds another level of complexity. Most inventory systems use a "weighted average cost" method of tracking the value of inventory. For example if I bought 10 at $5 and another 10 at $6, I have 20 kits with the average cost of $5.50 each.
Considering the idea of tracking Sierras by plating, besides chrome, there are maybe a dozen variations of plating. So now I may have one vendor offering 8 different platings. If 5 different vendors offer 8 platings, I now have 40 different inventories to keep up with. And if you track it by cost, the number of inventories expands.
And this is just for sierras.
Maybe you just need to know that the chrome Sierra is available from the different vendors or you bought the chrome Sierra from a particular vendor. Don't know, but be prepared for a mind-blowing trip when looking at how to build this inventory process. I've redone mine probably 5 times over the last 8-9 years.
I have Quickbooks setup to track total kits at an average cost but I do not care where I bought them from. The only care about where I bought them from is to know what I bought, how much I spent, and how the bill gets paid.
I tried to keep Quickbooks tracking kits by plating but found the logistics was too much. I had over 500 items being tracked by style and plating with a similar number of finished products. Way too complicated for tracking purposes.
I simplified the accounting by saying I have all sierra kits in one tracking number with three finished products...Sierras, premium sierras, and select sierras. Each of these three is based on the level of the blank and plating cost but each of the three still has a weighted average cost applied to the sale.
If I need to know how many chrome sierras I have, I look in my storage box. If I don't have enough, I order more. But, my inventory system should say how many total kits I have in the box of any type plating.