
If you have questions about the conjugation of скупщик or Russian nouns in general, you can practice and get feedback from a professional tutor.
Я так от этого устал: легавые, мафия, скупщики краденного...
I'm tired of not understanding things. Cops! Mafia!
Местные беспорядки коснулись и скупщиков рыбы.
Their earnings have been cut in half. Only the good-for-nothings are left to work.
Без скупщика эти камешки не стоят ни цента.
As things stand, it's just so much junk.