I always wondered... are these sold to your contact by playmobil, are they given away? how do they forbit selling of these in one country and allow it in another? 
I always wondered how people come by these... its impossible for us.
As far as I know, the "official" geobra position on these different items is as follows:
"Schaukasten"-Display can be sold by the retailers (who order them and probably pay for them) or sent back to geobra after some time (when the theme is no longer new).
"Aufsteller" (the cardboard-stands where the boxes - or catalogues - are put on) are not meant to be sent back and can be purchased by customers (I have actually been offered one once that was almost empty but in good shape after asking politely what would happen to it).
"Big klickys" (they come in at least two sizes 85cm and 160cm roughly) are NOT meant to be sold and HAVE to be sent back to geobra...
BUT: Some shop-owners seem to find a way around that (reporting the klickies damaged, stolen or missing maybe) or there may be exceptions for some types of them AFTER the theme has completely gone out of production.
These are my experiences with these items so far. Some of it is guesswork.
PF
