Blampop

OK, I know this is "Euro"-Bricks, and an old thread. But since it comes up on a google search, I thought I'd leave a note... In the US we have The Right of First Sale: https://en.wikipedia.org/wiki/First-sale_doctrine If you buy genuine lego parts, from an authorized retailer, customize it, and then sell it to someone, you haven't broken a law. But, if you were to do it on a large scale, or otherwise try to sell it as a genuine (non-custom)/ LEGO endorsed product, then, you might have trouble. Check your local laws. :)