We've just developed an intergration with Survey Monkey to collect survey data and output it to PDF and push the PDF into HubSpot. And we've done other integrations with WordPress, MYOB (accounts) and other systems. I've had a look at Navision and it looks like lots of data is accessible via the API.
Happy to have a chat to find out what you need.
Send me a private message with your email address and I will send you a meeting link.