All I can figure out, is the name on the top of the pink label which looks like Labitos Acquisition.
You mean that?
The last definitely is "Antiquitäten". And I read the first as "Sabatier".
Certainly you have a better view at the original than I have via the pic.
I also searched Google for a Auction in Verden/Aller and all I came up with is Horse Auctions.
Due to the (fixed) price label, I think it could have been sold at a regular art and antique dealer's.
Thus, I already guessed earlier, it could be Sabatier
But again, I only have to rely on the photo.