I appologize if this if in the wrong category but this seemed like the closest one to me.

As specified in the question, i need a service with an API that allows automated checks mailing. Here are the requirements:
- Requires minimum involvement from my part (my only task being providing the data such as the name and address of the people and the amounts to be sent)
- Requires nothing from the recipients (which means no sign-ups or or the need to provide a bank account number)
- A decent processing fee
- Also offers digital payments through services like PayPal.

If you used any services that fits this description and you were satisfied by it a short summary of your experience would be appreciated.

I would also need some recommendations of these 3 websites I found during my search for such a service.

1. batchex.com

2. webmasterchecks.com

3. chequeprintingcompany.com

Thank you in advance, looking forward to your recommendations.