Hi, Keith.
Yes. Go into Advanced Edit (the little notebook on the left side) on the question. Under, Advanced Formatting => Auto-Format, Do NOT set the radio button that says Auto-Format as Currency.
Then go to the box labeled 'Validation' and paste the following code in the box labeled 'Actual RegEx Pattern:
^\u00A3?([1-9]{1}[0-9]{0,2}(\,[0-9]{3})*(\.[0-9]{0,2})?|[1-9]{1}[0-9]{0,} (\.[0-9]{0,2})?|0(\.[0-9]{0,2})?|(\.[0-9]{1,2})?)$
Fill in the Message to Display When Not a Match so that your respondents know what they must do to move on.
Also, on the Advanced Edit page, set the question to be required. The question must be required in order for the validation to happen.
Be sure and save your changes.
I hope this helps,
Cheri