One thing you can do to help with comfort is put any rugs, blankets etc you can down on the floor especially where you are sitting. Cold comes up thru the floor and even in an insulated unit, the floors transfer cold to you. Adding another layer of anything between the outside and you will help. Make sure you put something in any vents or skylight areas to keep from losing heat thru them. We found that sofa pillows were exactly the size we needed to push them up into the vent openings and easily removed if the sun is shining to let the warmth in. Add curtains over day/night shades too. I used a tension rod (cheap) pushed up under the valances with the curtains hanging from that. The heavier the fabric the better for you.
