|Description||Optional parameter used for creating a subscription. Represents the amount of the first installments of the recurring payment.
The number of these first installments is defined by the vads_sub_init_amount_number parameter.
This amount is presented in the currency defined by the vads_sub_currency parameter and is expressed in its smallest unit (cent for euro).
E.g.: for an amount of 10 euros and 28 cents, the value of the parameter is 1028.
The value may be empty but cannot be negative or equal to 0.
Input and output field, returned in the response (IPN and Return URL).