Below is a quick list of the fees charged by PayPal, Google, and Amazon to process payments and store the value until transferred to a bank account.

Paypal

• 2.9% + $0.30 to receive payment from paypal funds or from a credit card

Amazon Flexible Payments Service

For Transactions >= $10:

• 1.5% + $0.01 for Amazon Payments balance transfers
• 2.0% + $0.05 for bank account debits
• 2.9% + $0.30 for credit card

For Transactions < $10:

• 1.5% + $0.01 for Amazon Payments balance transfers
• 2.0% + $0.05 for bank account debits
• 5.0% + $0.05 for credit card

Checkout by Amazon

Full-feature shopping cart, order fulfillment.
For Transactions >= $10:

• 2.9% + $0.30 for all transactions

For Transactions < $10:

• 5.0% + $0.05 for all transactions

Google Checkout

• 2.0% + $0.20 for all transactions

Analysis

For icecondor's monthly subscription of $2/month, the costs are $0.358 for paypal, $0.15 for Amazon FPS and Checkout by Amazon, and $0.24 for Google checkout. If I had to ship physical items I would look closely at Checkout by Amazon since order fulfillment is time-consuming. The icecondor service is virtual and Amazon FPS is what I'll go with. I wanted to use FPS anyways - it looks the most technically progressive.

Why not authorize.net or one of the other more traditional payment processors? I would have to be a VISA merchant which is a lot of complexity. In browsing the fee schedule for authorize.net i see a setup fee (not listed), a monthly gateway fee (costs $ whether you make transactions or not) (also not listed), extra fees for fraud detection, etc. Wow. I didn't realize its that bad. Like all of the Amazon web services, its strictly pay-as-you-go. Its payment processing 2.0.