Davy Select- Foreign Currency Transaction Charge

[BIG-notorious]

Does anyone with a Davy Select account know the typical actual charge, as distinct from the typical maximum charge? In the terms & conditions for this it says "typically the percentage adjustment will not exceed 1% of the total of the sale or purchase amount" which reads like an effective ceiling as opposed to a normal charge. There's no indication as to whether it's applied equally to all currencies.

Also, how is this applied in practice? Does it matter if I buy shares of a US company from the US, UK, or German stock exchange?

Thanks.