As thebax2k7, I sold quite a bit of rpg items on Ebay several years ago. There are several things to keep in mind when you are shipping: the weight of the item, the size of the item, and where it is being sent. Since you are selling Legos, weight might not be a problem (although if you will be shipping several thousand Legos to a buyer, than it will be).
Since I see you are in Canada, go to this website http://www.canadapost.ca/cpotools/ap...execution=e1s1 and type in the weight and dimensions of what you will be shipping. Knowing how big and how heavy your packages will be is vital, since you can then calculate your shipping costs. Very heavy packages and very large packages can get very expensive to ship, make sure you check out shipping costs with Canada Post, Fed Ex, and UPS--I used all three at different times depending on the destination and the package being sent.
I don't know if the Canadian Post has a flat rate box similar to what the US Postal Service has, but if it does, you may want to break out your collection into lots that will fit the flat rate boxes that are available.
Make sure if you decide if you are going to be selling to international buyers or not, costs also significantly escalate once you start crossing borders. The Canadian Post site I gave you will enable you to calculate sample rates to Europe and Asia, but make sure you tell International Buyers that you will promptly quote them or calculate an example rate after punching in shipments to several countries on the same continent (for ex. for Europe if an 8 pound package ranged from $30-45 US to send to various countries, I'd quote $45-48 to ship it to Europe, extra was for the cost of supplies. If you have several thousand worth of Legos that you will ship, I would recommend investing in a postal scale. I did (it was about $40-$60 US) and it more than paid for itself.
One last bit of advice, Ebay may no longer allow it, but pay for tracking and include it in the price in your shipping! It will save you so much grief. I shipped Super Nintendo games to a person in Calgary who disputed receiving them, thanks to Canada Post, I could prove that a package weighing X had been delivered to their address and had been signed for by X, enabling me to win the dispute. Most buyers will be honest, but every now and then you have to be wary. Also, be careful shipping overseas, certain destinations in Eastern Europe, Africa, and Russia can be problematic.
For more help, go to:
http://pages.ebay.com/sellerinformat...pingtools.html
http://pages.ebay.com/help/pay/quest...alculator.html
Hope this helps RobA, good luck selling.