We have a site where a user has to fill out series of forms including personal details for purpose of employment screening.

At the end of the process (or the user journey), we'd like to provide the user a suvery to gather feedback. Something simple, 3 questions. 

Approaches we are looking at

* On the final screen, provide a form approach.
* On the final screen, provide a link to third party site like surveyMonkey.
* We have the users email address, so on completion we could send an email with a link to a survey

What is the best approach that balances high engagement without annoying the end user? Is there a better way that I've not thought of?