Cover donation fee
Add the tag "Admin Cover Fee" to any donation_v2 page, to add the checkbox "I’ll cover the processing fee - add it to my donation" to the bottom of your donation form.
This will then calculate your payment processing fees and add it to the donation value that your supporter has selected. Note that the processing fees are calculated at the rate of 2.9% + 30c*
* or .3 of whatever unit of currency your site is using