Snazz Industries

Now that you have pulled out anything that has been built, its time to get your hands really into that pile and amass the true value. Hopefully, you were able to find a few figures and a few sets that were not complete earlier, and you have a general idea of what you need to look for. To start, dump the entire bin out. Every single piece, put it on a nice large sheet (bed sheets work great for being able to dump all the pieces back in the bin later). Start in one corner, and shift through the pieces. Take out (in order of priority):

Now that you have all your supplies, its time to start seeing what is valuable. I suggest starting your assessment with the assembled sets, because then you'll have a better idea of what you need to find going through the bulk pieces. If you are simply dealing with a massive bin of unbuilt pieces, skip this day and move onto the next post.

This step is based on intuition. The more you eyeball Lego sets, the better you will get at identifying them. If you have some experience with Lego, then you will be able to identity key themes like Star Wars, Harry Potter and Indiana Jones. Take each assembled set and take a guess at what theme it might be. To get an accurate set number, which will be necessary to sell the set and see if pieces are missing, go to the Bricklink catalog and try to match up your set with one in the theme you guessed. Once you have a set number, this will make it much easier figuring out what pieces you need to complete the set, and how much it will sell for down the road.

With a set identified, the next step is to figure out its worth and its completeness. If its a valuable set, it will be worth your time to hunt around for the extra pieces to complete it. Most of the value of a set also rests in the minifigs--although we will cover minifigs later, make a note of what minifigs the set has and set them aside. Keep a running tally of pieces and minifigs to look for, and this will make the next steps much easier.

So you have a Lego collection of bulk pieces in a massive bin in front of you, waiting to be sold. Great! This week long series will take you through the ins and outs of making the most from your recent acquisition.

Day One, you are going to need to get the supplies that you'll use throughout the rest of the week. There's no point needing to interrupt yourself later getting supplies, and this will help you get organized. Three things need to be purchased to ensure a smooth packing and shipping operation: boxes, bags, and tape. Once we have these essentials down, we can move on to more interesting things.
Boxes
Pro Tip: No need to pay for boxes. Assuming you live in the United States, you can get all the free boxes you'll need and have them show up to your door the next morning. Load up on some Flat rate boxes as well as some normal priority mail boxes. Depending on your collection, you might need more of a certain size. Lots of completed sets? Make sure you have plenty of medium boxes. Lots of minifigs and accessories? Get lots of the small boxes. Luckily, these boxes ship fast so you can always get more quickly when you need them. Keep in mind that the Post Office is stringent about how things ship. Once you pack something in these boxes, they have to ship Priority Mail. I'd also get some smaller bubble mailers via Amazon for smaller things, like individual minifigs, which can then be shipped more cheaply. Another important note: start stockpiling newspaper, which can be used as packing materials. There's no point paying for bubble wrap when newspaper works just as well.
Bags
You'll need ziploc bags for organization of pieces and figures. In my experience, I used three sizes of bags: minifig sized, sandwich sized, 1 gallon sized. 1 and 2 gallon will be used for broken down larger sets and bulk pieces, while sandwich bags will be used for groups of figures as well as smaller sets. To give you a rough estimate of how many you'll need, 1 gallon holds roughly 2.5 pounds (1.1 kilo), and the 2 gallon bags hold just over 5 pounds (2.2 kilo). These can be purchased online, although I was eager to start and just went down to my local grocery store.
Tape
Almost done. You just need the tape to close the boxes. Get some packing tape and some regular invisible tape, if you don't already have some lying around. The invisible tape is great for sticking on prepaid labels, rather than wasting the larger and more expensive packing tape.

Finally! Time to move onto the exciting things.