Google invoice via API
From: http://code.google.com/apis/checkout/developer/Google_Checkout_Comparison_Part_I.html
Request for payment on postal bills What is this? Mail billing allows you to sell without an online store. Buyers may place orders from you by telephone, fax, email, or other offline means; then you send invoices from the Merchant Center to customers requesting payment. Email invoices contain a personalized message from you about the requested payment, as well as a "Pay now with Google Checkout" link. When customers click this link, they will be taken to Google Checkout where they can complete the checkout process. Best of all: use this option if you don't have or don't have an online store. Time Required: No setup - just open a Google Checkout merchant account and you can start sending invoices right away. Required technical skills: None.Just internet access. Demo: Invoice and Master Email (registration required) Processing Orders: (Part II). When orders begin to arrive, use the Merchant Center to pay for orders and update your order. Next step: how to request payments for e-invoices
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From what I've seen, it looks like they don't have a way to do this via the API. Hopefully someday they will, but for now I think I will need to create my own email address with a link to my own page that will submit them to Google Checkout via a custom Buy Now button.
Too bad - it would be easy to just call send_email (name, email, quantity, message) and do it in the same way as logging in and running through the Merchant Center.
I understand the logic a bit - if you are capable of creating an automated billing system that can call the Google API to send email, then you should also be able to create a link, a custom button and allow the user to check out that way. I still want it - I'm lazy.
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