here's a real-life example. one platform charges $23 to process a $500 donation [$3.15 for a $50 donation, $5 for a $100 donation, $9.50 for a $200 donation] plus Stripe fees. based on a $500 donation, that's $23 not reaching your mission.
with gvr.'s one-low fee of $1.50 for donations over $5 [donations $5 or less are FREE], an extra $21.50 from a $500 donation would go to your mission. and that's where the funds should go!