I'm home from a tour that was half camping, half not, and it's woefully apparent that my 3-season tent (an REI half-dome) won't cut it in the winter. Yes, I bundle up inside my sleeping bag, and sleep with a balclava, jacket, scarf, et cetera, but it isn't enough. (The temperatures went down to just above freezing.)
A sleeping bag liner may help (I borrowed someone's extra sleeping bag one night, and it helped a little), but since I sleep on my side with my arms out of the bag, I'll need a warmer tent. 4-season tents seem to go for $500 and up, and I really don't have that kind of money right now.
Is there anything that can be done to winterize a tent, similar to putting a liner in a sleeping bag?
Has anyone used a light sleeping bag with a liner for winter camping? How did it work out for you?