Stormonu
Legend
I tend to buy only the official Core books (PHB, Xanathers,Tasha's, DMG), and official & 3rd party campaign books that interest me (Theros, Eberron, Ravnica, Tehautl & Chronicles of Aeres). When it comes to monster books, I buy any I can get my hands on, WotC or 3rd party. I only buy adventures I plan to run (Curse of Strahd, Ghosts of Saltmarsh).