diff --git a/src/command.h b/src/command.h
--- a/src/command.h
+++ b/src/command.h
@@ -212,6 +212,6 @@ extern const char* _cmd_text; ///< Text,
 
 bool IsValidCommand(uint cmd);
 byte GetCommandFlags(uint cmd);
-int32 GetAvailableMoneyForCommand();
+Money GetAvailableMoneyForCommand();
 
 #endif /* COMMAND_H */