So do you use FB Ads only at the top of the funnel or do you also have have retargeting Ads? Just curious as I'm in the process of setting up this very process myself for https://redokun.com
Both. Mostly I send people to blog posts that contain some sort of an email optin in. But I've also regargeted website visitors via FB's pixel with good success.
All-in-all, I'm fan of "slow sell" via an email newsletter and FB's been great for getting people onto my list.