What hose is needed to convert to 100 lb Propane tank

Just go to a propane distributor and lease a 100 GALLON tank. the distributor will bring the tank to your site, hook it up for you, and fill it. When it gets low, he will come fill it again.
We lived in a 32 foot triple slide fifth wheel through a Montana winter with just such a setup. I don't remember how often we had to get the tank refilled, but IIRC it wasn't all that often.
It worked a LOT better than hauling the 100 pound cylinder to get it refilled like I did during a previous winter!