Yes I agree $399/mo is a bit steep for a simple form but it was an option if it worked for you.
My practice is to simply create the form in Kentico, let the customer submit the info and Kentico handle all the email notifications. Then created a scheduled task to run every hour, 6 hours, 1 day, whatever your requirements are, and call a web service and write the new form submissions to CRM. In your form, add a field called IsExported and update it when that record is exported to CRM.
V8 docs: https://docs.kentico.com/display/K8/Scheduling+custom+tasks
V7 docs: http://devnet.kentico.com/docs/7_0/devguide/index.html?scheduler_overview.htm