Preparing to live out in a car for a couple of months is one thing. Living for a longer period like 6 months or year is entirely different, especially in cold weather. Unless you feel that a job plus rental is absolutely not an option, I'd advice against it.
I have known people who lived for 6 months out of a car, in Southern California, where the weather is the mildest (the best anywhere), and it still was very hard. Even Texas can be very cold in Winter, with temperatures dipping below freezing in the middle of winter.
I prefer being a camper, to be honest. If you're serious about it, I'd advice instead that you do two things:
1. Consider slowly making your way south as the year progresses. SLOWLY. Not in winter like you say, but also migrate during fall/spring. Why not plan to go to California or Florida for the winter? Since you are not tied to anything why not just keep moving?
2. Try to see if trading for a larger vehicle where you could sleep/camp is an option. A large pickup truck with one of those Fiberglas covers with windows, whatever you call them. In the future perhaps the camping type pod could be fitted to the same vehicle.
Another reason to move out west outside of urban areas: Cops will harass you when they see someone living out of a car in a street. No one will harass you at a camping ground.
Go visit Colorado. Who knows? You might find loving the outdoors, and settling eventually with a job in a smaller town out in the Wild West.
I know if I absolutely had to live in a vehicle, I'd definitely be going west to where the greener areas are. I wouldn't mind settling in an outpost working in a tiny shop living from the tourism traffic outside one of the major National Forests.
Something like a clerk at a convenience or souvenir store, selling Native American trinkets to corny tourists

I could even dress up as a Steampunk all year round. With my uniform, I'd fit the environment rather nicely

At least, when my time comes, I'd be happy to die out there, rather than contemplating a hospice in the city.