CotW is famous for deep discounts during Steam Seasonal Sales, where DLCs often drop by 50% to 70%.
These are unlocked by completing difficult story arcs in the base reserves (Layton Lake and Hirschfelden). 4. Modding and "DLC Unlockers" (The Risks)
To understand the desire to "unlock all," one must first understand the game's economy. Call of the Wild utilizes a hybrid model: a paid base game with free updates, supplemented by paid DLCs.
Start with the base game. Buy (Crossbow) and "Silver Ridge Peaks" (best beginner map). Unlock the rest over time.