Gas vs electric cost calculation?

If you have an extend a stay and or they deliver propane to the site I might use more propane. If I have to un hook and go get propane it would be worth 20% more not to half to. Keep in mind if you do start your rig you need to drive about 20-25 miles to get it up to temperature. Now figure the added cost of fuel how does that work out. If I have an extend a stay and a 30# tank It might be cheaper to use more propane.
Bill