A family plan says it's $23/month. That's well over the cost of a 3 lb tin from Costco ($18.69 by me), which is several weeks if not a month of cold brew.
We're kind of getting off track here, but a 3-lb tin of preground coffee is not going to taste very good by the time you finish it, if it ever tastes good at all. It's pretty likely to be low-quality and stale before you even pull it off the shelf.