Recurring payments profile ID returned in the CreateRecurringPaymentsProfile response.
Character length and limitations: 14 single-byte alphanumeric characters. 19 character profile IDs are supported for compatability with previous versions of the PayPal API.
Note: The profile must have a status of either Active or Suspended.

The amount to bill. The amount must be less than or equal to the current outstanding balance of the profile. If no value is specified, PayPal will attempt to bill the entire outstanding balance amount. Character length and limitations: Does not exceed $10,000 USD in any currency. No currency symbol. Regardless of currency, decimal separator is a period (.), and the optional thousands separator is a comma (,). Equivalent to nine characters maximum for USD.

A three-character currency code. Default: USD.

The reason for the non-scheduled payment. For profiles created using Express Checkout, this message will be included in the email notification to the buyer for the non-scheduled payment transaction, and can also be seen by both you and the buyer on the Status History page of the PayPal account.