So obviously 4,000 pounds would be minimum amount I'd need for the rest of the winter, but I could easily use another 8,000 pounds if things get serious. Now that's not actually that expensive. 100 pounds is about $9.45. But I do have to get the things, load them, store them somewhere, and then treck them across the yard in the middle of the winter (no doubt while there is snow on the ground), and then drag them down to the basement where they actually get burned.
So far I've done pretty good shlepping them down a somewhat narrow set of basement stairs, but that's been during pretty dry conditions. I'm not looking forward to carrying another 200 bags of pellets down stairs during a snow storm with a couple of inches of ice on the stairs. Sounds like trouble.