Currency toggle between Local, $, and € in a straight table

[Anuhyak1]

I have currency Toggle Local, USD,GBP. 

If user selects Local  textbox Sales value should be displayed with out $ and the expression for Sales Value := num(sum({<$($1)>}SLS_DLRS*$(vCurrency)), '$#,##0') Ex: 80642

If user selects USD  Sales value should be displayed $ in front of  num expression. Ex:$80642

If user selects GBP  Sales value should be displayed  in front of  € num expression.  -Ex: €80642

Local: For local text box just set two variables.

VCurrency=1

vCurrency_MSRP=LOCAL_MULT

For USD text box

vCurrency= USD_MULT
vCurrency_MSRP =1