Currency or monetary value in a form

[Guest Paul Alexander]

One of the questions in one of our forms asks for the 'turnover' of a company, which I've set to be a digital field, but which I need to be in a currency format (i.e. £300.00)

I know I can use regex to ensure that they customer always adds a '£' sign and some numbers and then adds 2 decimal places, but is there a way to add an input mask of some sort so that, if they add (for instance) 300 in that same field, it gets converted to £300.00 automatically? 

I've set up a concatenate node in the BPM to update this value in a custom field, but this doesn't update that same value in the 'questions' section of the request, which is where the analyst normally gets this info from. 

So, 2nd question is, is there a way, through the BPM, to update the value in the Questions section of the form based on the update node described above?