Q:

How to override amount in PayPal hosted button (recurring payments)

I have a client that uses paypal to capture recurring payments.  Their previous developer set up a hosted button for each subscription type which is chosen by the user from a series of 3 dropdown menus.  There are 3 different subscription lengths each with their own dropdown menus with multiple selections, however when sent to paypal, it's literally only 3 different payment amounts.  Why a hosted button was setup for EACH POSSIBLE combo is beyond me, but it's what I have to work with.
My problem is now the client wants to accept coupons/discounts and wants the price subtracted before the user sees it on paypal.  This is easy enough to do dynamically (they will have multiple coupon campaigns going at once), IF I were generating the button code, however all I have to work with is a string:
https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=2FSZJAH95MJL4

or similar... 126 of them to be exact.  I've tried simply passing the new amount over in the query string, but it's ignored.
https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=2FSZJAH95MJL4&amount=9.99

I don't mean to be dense and this is my first time posting, but I'd like to know the answer to this one.  How do I send a new amount over to paypal with hosted buttons like this?

A:

It is not possible to update/change the amount in hosted buttons dynamically, you will need to login to www.paypal.com to update the hosted button information or make use of API to update the hosted button.
To overcome this you may need to use Clear text buttons(which is not hosted).

