going to move to northern cali next weekend and i plan to stay in my car(4 door tacoma) until i find a place to stay. my car doesnt have a heater so i plan to use a portable propane heater. i know i must vent. been looking at coleman catalytic heaters ranging from 1000 to 3000 btu. will 1000 btu be enough. or should i go with 3000btu. would appreciate advice and tips from anyone whose done this sort of thing

pic slightly related. it can get pretty wet in eureka