We have the extend stay and would not be without it. The main tank holds about 18 gallon give or take. I hate when we're camped like now to have to pack up and move every time we need propane. I have a 30# we hook when we plan on staying for a while and if need we use the grills 20# while I get the 30# filled. Right now with day temperatures below freezing it's about every 6 days to refill the 30#.
We're waiting for the wife to finish up her Chemo treatments which will be just before Christmas before we can head south to our Daughters in KY for Christmas and with God's blessing the DW will be in remission again.