One of the absolutely best advice given to me by experienced AFOLs early on this project, was to use the BrickLink marketplace for my brickquisitions, and so I have done when acquiring parts for the 6080 King’s Castle. I have also used the official LEGO Pick a Brick store, where you can get new parts (on BrickLink there are new and used parts), but that is less useful for classic projects that require old parts and especially old colors. At BrickLink, you can search for particular parts or for example browse by color, which I have found very helpful. A couple of issues have haunted me when using BrickLink, though.
Minimum buy is one of them. While I can understand why sellers require a minimum commitment to justify the trouble of picking and packing, it has made my life quite a bit harder when trying to place orders. For example, the classic castle grey (called light gray on BrickLink) may not available in very large numbers at particular sellers, which means I may not be able to buy as many as I’d like, and even when availability is sufficient, my current needs are pretty small. Also, individual bricks are overall quite cheap, which means that meeting the minimum requirements has sometimes proven impossible unless I’d go ahead and order a large bunch of bricks that I don’t need. Some sellers have a packing charge for very small orders instead, an option which I’d actually prefer over ordering more bricks than necessary. Sometimes paying a bit extra for the flexibility is fine.
The other hurdle is finding the suitable seller for the multitude of 1984 castle parts I need, ones that are also located near enough and ship to my address, and preferably have lots and lots of good feedback to show a reliable track record. More experienced buyers probably know how to navigate between the various brickshops, and know which ones to use for whatever they are currently building, but I’m not there yet. Luckily BrickLink’s Items for Sale list shows the minimum buy, seller location and feedback right there on the list. I’ve usually gone ahead and searched for one particular brick I need and then gone through the Items for Sale list to find a suitable looking seller, and then clicked the Go Buy It link for the shop’s BrickLink pages to see if I can sufficiently fill my cart there.
But even with this method I often notice that the particular seller does not have everything I need and then I either order partially or go back to square one. Thinking that there must be a solution for this, I explored BrickLink a bit and came up with something promising. On the top bar there is a tab labeled Wanted. Clicking it takes you to your wanted list – you need to login for it to work, though. You can add bricks, minifigures or other gear to your wanted list one by one, or you can click sets and browse almost the entire history of LEGO sets and add any of them to your wanted list. You can then view the set inventory by clicking Inv or add the set to your wanted list with Add to My Wanted List. Once added to the wanted list, BrickLink automatically shows you all the sellers with the wanted goods.
Most importantly, clicking Part Out next to Add to My Wanted List should let you add all or some of the individual parts of that set to your wanted list. Unfortunately when I tried this, it ended up in a server error, as did browsing the wanted list By Shop with multiple selections, but on a good day this should be invaluable help in avoiding the hurdles I mentioned above. There is even an option to notify you by email when a hard to find brick finally hits the marketplace. Sellers can also use the same functionality to upload and part out their sets to BrickLink. Finally, there are statistics available of the most wanted sets and parts. Interestingly the most wanted set seems to be the 10182 Cafe Corner and the most wanted part a black Technic pin with friction ridges lengthwise and with center slots.
Similar functionality can also be found on Peeron, which allows you to not only browse parts lists for various LEGO sets (here is the list for 6080 King’s Castle), but also to match those parts lists with your existing sets to see which parts you already own. Indeed, I have peeked Peeron on many occasions to see what parts I may still be missing from the 6080 King’s Castle and which I already have based on some of the major childhood sets I own.