Treat economy features as financial state​

Player balances, trades and rewards must remain consistent after repeated clicks, disconnects, restarts and database delays. Identify which plugin owns the balance, which plugins only present or move it, and where transaction history is recorded. Vault usually provides an integration bridge; the connected economy remains the source of truth.

Design before deployment​

Model currency sources and sinks, set limits and cooldowns, document dispute handling and test duplicate-event protection. A polished GUI does not replace atomic debit and credit behavior. For network servers, confirm whether every backend reaches the same authoritative data store.

Choose by use case​

UltraPAY focuses on payments and history, Billford on controlled trades, Bounty on player targets, and investment or shop systems add distinct progression loops. Avoid installing overlapping systems without checking how their rewards affect inflation.