What are good payment services (such as https://www.alertpay.com/en/Default.aspx) ?
The only requirements are: - the webshop is located in Europe - the revenues are around 30.000 40.000 euros per week
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A list of gateways I found, sorted by country:
I get the impression that Authorize.Net is the most popular one, starting at $20/month or something like that.
Would probably be a good fit with Shopify.com .
Did you try considering Paypal or Google Checkout or Amazon Payments . I know that Amazon Payments exist in the US, but not sure if its present in Europe
In case you are selling software, you should look into fastspring.com