UK broker isa. US currency charge


Hi all.

Looking to improve current broker. I trade within an isa on stocks only. My strategy involves fairly tight stops at 2 to 8% and position sizing accordingly.

I currently use td direct / now ii which is great for UK stocks with high liquidity and tight spreads.

Problem with US stock as their currency charge/ spread is 1.5% above market. Meaning I have to allow and extra 3% on position sizing calc as you cant hold foreign currency in isa...

I also keep a portion in vanguard lifestrategy fund for my son long term ( hes 3...)

Currently looks like most uk brokers do charge 1% to 1.5.

Ig being exception at 0.3% but they dont do also looked okay but again no funds and interactive brokers don't do isa's....

I probably already know the answer that should go ig or saxo and perhaps transfer sons isa fund to mothers isa but thought people here might know another options?