I’ve been asked many times about how I track our inventory of LEGO® elements. The fast answer is “very carefully”. The real answer is a little longer.
The “primary” inventory of what we have is kept via BrickLink. As I write this, that’s a total of 266,086 items currently listed for sale, so there’s a lot to keep track of.
What about new inventory? New inventory gets uploaded via another indispensable tool of the trade: BrickStock. BrickStock works with BrickLink to make available inventories for sets. When I started parting out 10 copies of set #41313 this morning, I first went to BrickStock. I had the program part out the set and told it I wanted to do 10 copies. Voila! A complete list of all the parts and quantities I expect to be in those 10 boxes. A moment later and I have the prices set to the 6-month average sale price, and another moment to adjust all these prices to our store prices (we currently sell most items at a significant discount to the 6-month average sale price).
But before I go uploading this to BrickLink with the assumption it’s all there, I actually part out the sets. One bag a time, I sort the pieces into cups. Before I put the parts away, I’ll count every cup to be sure I have the right number. Sometimes parts get sorted wrongly, or stuck in the bag, or (very rare!) I’m missing a part from the set. After checking that I have the correct number of parts, I upload the parts into the BrickLink inventory from BrickStock. This painstaking counting helps assure that I’m not listing for sale more of any part than we have.
When we have orders, the parts are deducted from the inventory automatically on the site where they were purchased. BrickSync then goes on to make the same correction in the inventory on the other site. After we count out the parts for an order, if the number of remaining pieces isn’t too large, we also count the pieces still in stock – both as a check on our counting of the order, and as a check on our remaining inventory.
In the rare instances where we do have an error and we’re short a piece, we always have other sets waiting to be parted out. We first check those sets to see if we can make up the missing part from one of those sets. If we can’t, we contact our customer ASAP to let them know and resolve the situation.