I paid $700 7 years ago for a double 16'x7' roll up...which included the upgrade to the heavier gauge of steel....that was installed.
In retrospect I wish I had also taken the option for insulated doors...not because of temp, but for the noise. The inlaws have the insulated door and it cuts down on the noise as it goes up and down by quite a bit.
As soon as my new garage is done, I'm going to replace the steel rollers with nylon wheeled rollers.