Myself, I don't usually keep a lot at hand because it takes a lot of room. That said I have about 136 pounds at the moment. This because I got the deal at Lowe's and I also need to feed a hungry 22 WSM .
I'm kinda ashamed to admit it, but I have two 20# bags of lump and 1.5 bags of Kingsford Charcoal. However, I live just down the road from the Kingsford factory...they have torn bag sales every week