Paypal Labeling

This plugin works wonderfully with paypal. However is there any way we can add tags to the paypal field?

This way it will be easy to filter out finance with paypal.

My Problem:
I use this plugin to create multiple service forms with paypal.
On the Paypal end I have the payments without any problem.
But at the end of the month it is difficult for me to manage invoice based on services because there is no label on invoice to filter it by.

If I can adda tag in paypal field by which I can filter out paypal invoices, that would really helpful.