If you've bought a VanMoof second-hand, it's important to know whether the bike was stolen or not. Please check the frame number with your local authorities. Most countries have a website where serial and frame numbers can be checked to prevent fencing. The frame number is stamped on the bottom of the bike, between the pedals.
Once you've made up your mind about buying a second-hand VanMoof, please keep in mind that the person selling the bike needs to remove their bike from their My VanMoof account. When the owner removes themselves, they will receive an email containing an attachment which they can then send to the new owner. The attachment contains a validation code for the new owner, so that they can register the bike again and transfer the ownership to the new owner.
If the previous owner can't supply this validation code to you, please think twice about purchasing the bike.