I have asked around, with no clear answer.. I do all my shopping in Jestetten and Singen usually since I live in Schaffhausen. Since I don't have a car, nor wish to get to the car crossing border somehow. Where would I get my bill stamped then? How does this work when you shop with the train? There is a customs office in Schaffhausen. But do they honestly expect me to shlep my grocery shopping there every time? Not practical. I am going to ask at the SBB desk to see if they have some advice also. Any help would be appreciated.
In Konstanz you can get the stamps at the trainstation.
In BaselBad you can get the stamp when leaving the trainstation into Switzerland. I once manged to leave an incoming IC from Germany in BaselBad, get the stamps, jump into the tram, rush to BaselSBB and catch the train I just left to continue to Zürich, but I wouldn ́t recomend this. Very hectic, and still doesn ́t always work out.
In all other places you cannot usually get a stamp, at least not that I know of.
Option B is to get a stamp from the Germany embassy. But this is probably even less convenient.
In Chiasso the trains waits a little longer at the stop and you jump off and get your forms stamped. Then the guard asks you for your address to pay the Swiss VAT (if he catches up with you) and then trusts you that your address is correct.
Not under all circumstances. You can always get the stamp at the German embassy in Bern. But I guess that ́s mainly interesting in case of high value prices
EDIT: Not only Germany, by the way. Any EU-custom ́s stamp will do!
Why would Schaffhausen do it when they are not in Germany or EU. Much easier to just accept you are getting your shopping much cheaper the CH anyway and not bother with the stamp
You can only get the samp in schaffhausen if you drop it in the letter box.. I once dropped a value less the 300chf and they weren't too happy and gave me the stamps however..