I can't comment on prices because condition and other factors greatly affect price. Generally, Frommers are a bit on the rare side, but not "expensive rare". Different models of Frommers were manufactured in Hungary from about 1901 to WWII. The most common use of Frommers in WWII were the "Stop" and the "37M". Hungary was allied with Germany in WWII, and the German military took most of the production. In the German military both used 7.65mm Browning (.32 ACP) cartridges. Do you know the model? The 37M looks like a Browning type pistol with an extended toe on the magazine, is much more likely to be found, and was used largely by the Luftwaffe. lt is most likely to be the one you have.
The Stop is an odd-looking pistol that is one of the few to use the "long recoil" action, with a tube of smaller diameter with recoil springs atop the barrel, and an odd-looking external hammer that seems to be placed too low in the frame. The Stop is a bit difficult to field strip, and its design is much more complicated than any .32 caliber pistol needs to be. If that's what you have, I suggest not trying to take it apart until you've learned more about it.
Of the two the Stop is a bit more valuable, because it's a bit rarer, but unless there is something truly unusual about the pistol, neither is in the high price category. If you want to send me a Personal Message with a picture (or a fuller description) and a description of the markings, I'll try (no promises) to provide more details. David