Bricklink is perhaps secretly (or perhaps not) owned by LEGO itself so they can have their hand in the pocket of the used / resale market. People will upload full MOCs (My Own Creation) there and you can purchase the sets piece-wise. Usually even more expensive than if you wait and buy a set through LEGO but for stuff like this it's worth it.
Bricklink is perhaps secretly (or perhaps not) owned by LEGO itself so they can have their hand in the pocket of the used / resale market. People will upload full MOCs (My Own Creation) there and you can purchase the sets piece-wise. Usually even more expensive than if you wait and buy a set through LEGO but for stuff like this it's worth it.