Report Abuse. Dear Ro: The IRS charges a nominal rate in the area of 4-5%. If you can send a small amount, do it and then the IRS will bill you for the rest. To set up a payment plan costs about $105 so do what ever you can to avoid the installment agreement.You have until Apr 15 to get $700 together.eport Abuse. Dear Ro: The IRS charges a nominal rate in the area of 4-5%. If you can send a small amount, do it and then the IRS will bill you for the rest. To set up a payment plan costs about $105 so do what ever you can to avoid the installment agreement. You have until Apr 15 to get $700 together.