In business we call that a cost avoidance. Following the logic say on fuel savings the greater the distance you live from work the more money one would save. So if you live too close to work you may have a harder time cost justifying. The solution is to move farther away from work to get a greater savings.

If a guy is saving say $1000 per month by commuting and not having a car. He likes his home his wife works near home and his kids love the school system there. His company offers him new job in the location the other side of town being a distance that is impractical to commute by bike but he could easily drive in his commuting time now. The new job pays $2000 more per month. Should he buy a car and bike ride when he gets home?

Yes everyone has their own method of calculating it. For those that are 100% car free. I haven’t seen any mention of if a few times a year you have to rent a car for a vacation or anything like that. How do you handle the emergency days. If you sprain an ankle or something, super bad weather? Where I live we can wake up to 4 feet of snow on the ground at any time now.