Beth, it is so cold here that I am going through a tank of propane every 2-3 weeks. Last one lasted 17 days, but was only about 2/3 empty. And that is with two small electric heaters going almost all the time! With my old electric heaters, I used a tank in 15 days. I pay a flat fee of $55 per month for electric and it is not metered, so I am using the electric heaters as much as I can.
I will be happy to get back to Nevada and Arizona where I went through a tank every 2 months!