I've used that 2-burner Coleman stove quite a bit for tailgating at football games... I seem to think that one bottle of that fuel would probably not last 2 weeks, if you're running it up to 30 minutes every day.
But, my observation if far from scientific; it just seems that a bottle never lasted me that long. And, maybe I used more fuel outdoors in a windy parking lot... perhaps, you would use less fuel in a more sheltered location.

Our local Sam's Club store has 4-packs of the fuel bottles for $9.95 ... that's the best price I have seen.

Does anybody recycle those fuel bottles? That may be "forbidden" on the label (Ka-BOOM!), I have not looked lately.
It just seems that those metal bottles are too nice to just end up in a landfill somewhere.