I found that getting the script for the o2 from the doctor was only half the battle. The o2 company's around me either wanted charge me a tun of money per tanks monthly rental or said they do not service Cluster headache patients. I finally found one place that I could talk to and they worked with me, we found that it would cost me less money to pay out of pocket for O2 then it would if insurance paid for it. I get 2 m60 tanks filled 3 times a month for 90 bucks and I have 4 E tanks that cost 15 each fill. they come to my house and swap the tanks out. It took about a month of calling and fighting with different company's in my area but I just googled the list of places and started from the top. I drove and picked up my own tanks from a few places and tried to swap them out the next day and they upped the price because I was causing to much paperwork, I had one place that would not answer the phone when I called them after a few tank refills. You will come up against all kinds of things but if you just keep calling or have someone you know at a doctors office call for and with you you will fins someone that will work with you.