Formstack is one of the few form sites we have found that lets you integrate payment into the form with Paypal rather than the user being kicked out to Paypal's website. That is a huge time saver for us, so we don't have to spend time chasing down payments.
It is so easy to use. We set a custom template up with our branding and with one click we can drag and drop to make awesome forms!
Accepting Payments with PayPal We use Smartsheet as a project management tool. Integration with Formstack has allowed us to make better use of the system with our forms since Smartsheet doesn't have a robust form system. We do this integration through Zapier.