Heres what you should do to be safe.
On the user's settings/profile/whatever user page you have, add a cancel button. When the user clicks it say "are you sure? Yes/no". If the user clicks yes, cancel the account.
No extra hoops at all.
No extra hoops at all.
To signup they just went to foo.com and there was list of plans with links to their sign up pages right there, so click one of those, fill out the one page form, click submit.
To cancel, they have to go to foo.com, click the login link, full in the login form, click to submit, then on their home page click on the profile icon to get the profile menu, click account in that menu, and then click the cancel button on the account page.
That's 2 clicks to sign up and 5 to cancel--6 if the cancel button asks if you are sure.
To cancel: enter your email and password, cancel.
What am I missing?
Plenty of sites have a sign up button on the front page. That's going to take you to a form where you create an account and put in payment info. It's inherently a multi-step process since it requires multiple pieces of info.