FYI - The Instant Pot 6 Quart Duo (the one WITH the yogurt function) is on sale on Amazon right now ... $20 off with free 2-day Prime shipping!
I don't know when the sale ends. It doesn't say. But if you've been thinking about getting one, this is an awesome deal.
Edit: Here's a link. Hope it's okay to post. It's not an affiliate link. Just a regular link.
https://www.amazon.com/dp/B00FLYWNYQ