In-depth analysis of cost control and order execution efficiency in London gold and spot silver contract for difference (CFD) transactions. This article starts from the aggregated liquidity pool, dynamic and fixed spreads, overnight interest and slippage control, and breaks down the impact of the No Dealer (NDD) pass-through mode, low-latency data center and FIX API architecture on the transaction win rate, helping you to establish a refined precious metals risk control plan.