For Kristal AI, you are limited to those offered on their platform. If I'm not mistaken, the charge is USD 1 (+ taxes) per purchase. Kristal AI also charges a management fee if your account is USD10,000 of 0.30%. For FSMOne, the RSP is also limited to those on their RSP plan and with each purchase it is 0.08% or USD 1 (whichever is higher). As far as I know, holding ETFs are not subjected to custody/holding fees. For Tiger Broker, you can purchase any ETF on the US, HK or SG markets. Tiger Brokers charges about ~USD 1.99 per trade. Tiger Brokers does not charge custodian fees. If you're buying an ETF on FSMOne/Kristal AI's platform, it'll likely be cheaper to buy on FSMOne since they do not charge a management fee. However, if the ETF you're looking at is not available on either's RSP, then Tiger is way to go because Tiger has lower comms on normal ETF purchase. Hope this helps!