you can send it PayPal to PayPal and there be no fees if:
¶ you use the "Send Money" tab
¶ designate the payment as Personal (not Purchase)
¶ designate the payment method/funding source as either PayPal Balance or eCheck (not credit card)

P.S. if you mess up and there is a fee, you will see it before you make the final submission. Also. if you really mess up, you can have the other party easily refund the payment (there is an easy link for that) and then there will be no fee.

Robt.