USAePay is a payment gateway service provider allowing merchants to accept credit card and electronic check payments through their Web site and mobile devices.
Free Add-on to manage locations for your business built with WP-Invoice plugin.
Create recurring invoices all handled from within your WordPress control panel.
The Quotes Add-on let’s you automate your workflow by creating quotes and letting your clients ask questions regarding quotes directly on your website. Once a quote is approved, it is converted to an invoice with a single click.
Make you invoicing solutions more powerful with WP-Invoice and Power Tools. Sales charts, import and export ability!
Creates PDF versions of your invoices, receipts and that you can easily email and print.
Add-on allows you to extend your WP-Invoice based commercial website giving the new payment option like Mijireh.
Make your clients sign invoices before payment to get secure information that will confirm payment.
Makes it easy to create one-page-checkout forms that can accept a variety of different payment gateways, such as Authorize.net, PayPal and others.
PayPal Payments Pro has the customization capability, technical maturity, and proven security that is needed to build professional-grade eCommerce sites.