Just took a quick look at the Habitualist site. Not sure if it's intentional or not, but I found it a bit off-putting that you can't tell how much the plans are before you sign up.
Sorry, that was an unintentional side-effect of switching away from requiring a credit card upfront.
We'll put the information somewhere else.
Until then, for everyone else: it's $5/month or $50/year.