Were I to spend that much on something it would be a vierling.
The prices for (used) Vierlinge vary widely in Germany. They lowest start is in the lower four-digit echelon of €uros, and they are going up to maybe 8000 €. They are uncommon of course, but show up very regularly in auctions, online-auctions, and with dealers. You just have to keep in mind that the utopian asking prices of specialist hunting gun peddlers (such as Jagdhaus Wilhelmshöhe or Feine Waffen Norbert Wenninger) are *in no way* even remotely linked to the actually PAID and realized prices on the market.
Also, one must be aware that Vierlinge are but (expensive and somewhat exclusive) Toys for Old Boys, but they are not really very useful, nor practical, nor do they shot together. Even in the Olden Times (the Golden Age of Suhl and Zella-Mehlis), there were expensive Vierlinge and those on lower rungs of the ladder. Even Burgsmüller (Kreiensen) offered Vierlinge as cheaply as he possibly could, as proprietary trade guns under his name, in his big mail-order catalogues and sold quite a number.
One such Vierling (made in Zella-Mehlis) was just auctioned here via eGun for 2010.00 €uros, here is the interesting link:
https://www.egun.de/market/item.php?id=20132542 (temporary link)
https://waffenhandel-zwack.de/burgsmllerkarlsenkreiensen (permanent link, scroll down the page)
Condition is still okay (metal mediocre, old and much-used oily wood), engraving quality is LOW, certainly not even on a par to Walt Disney. But a nice toy nonetheless.
Carcano
(who just has bought an almost pristine, almost unfired Christoph Funk Drilling from the 1930s)