As you all know when you have an expression and you try to format the numbers inside the box by right clicking on the box/field and then hitting Text Box Properties, that formatting does not always work especially when you have text too in that expression.
So here is the solutions:
=Format(Fields!Somefieldnamel.Value, "'$'0,,.0") In my example the formatting is:
Currency:
Symbol: English
Show values in: Millions
Decimal places: 1