I remember during our internship year specifically, staying home for what felt like the entire year. I noticed something, that is probably just common sense to everyone else: every time I left the house I was spending money. I am not talking about getting in the car and going somewhere TO spend money in exchange for goods/services. I am talking about every time I turned the engine over I was spending money.
No longer was just going for a drive a free way to pass time, it was money that we were literally burning without receiving anything in return. When I did venture out it was never to only one place. I have noticed as our children have increased in number, and we have a small baby, that it is more difficult to do more than one thing with each outing, but I still try to make every trip count. DrH even helps by calling on his way home from work to see if we need anything from the grocery store. Anything to avoid getting in the car when it isn't absolutely necessary.
When I think about the particular cost of things I also use the amount of gas in my equation. For example we have a family membership at the local gym about 7 miles from our home. Our membership fee is $58/month. And we use every penny of that and then some! They offer free fitness classes, free swimming lessons for the kids, and 2.5 hours of free babysitting every day. Of course, I don't actually use all that time every day, but when mama needs a break it's nice to know I have somewhere to go. But in going to the gym I am spending money in the getting there that makes my gym membership more around the $85/month mark if I only go 3 times a week. Some months I go more often, making it more expensive. I think I just successfully talked myself out of working out!
When thinking about a home to rent (or purchase, if you must) consider the cost savings that will come by living in a location that is convenient to the hospital, a grocery store, a gym, the library, your church, and any other establishment you believe you will visit often.
Living close to these amenities will enrich your life in two ways. One, you will spend less time in a car getting to were you need to go. This could be particularly important for your DrH who will be tired and your family who will want to squeeze every available minute out of your time together. Two, you maximize your dollars. Every dollar you don't spend in getting somewhere is another dollar you have to spend on something you might need or save for something you will need (and you will need something that even your best budget will not predict).
When the gases prices move like they have recently it makes establishing and sticking to a budget more difficult if you do a lot of driving. By living close to the services you use the fluctuations in gas price won't hurt nearly as much. You might also be able to have just one car further adding to your savings, by not needing to insure a second vehicle.
Some fuel for thought: when we started internship/residency the cost of gas was $2.59/gal. Today's gas price of $3.79 represents a difference of $1.20. It may not seem like a lot but multiple that by the 80 gallons of gasoline we consume between our two vehicles and it represents an extra $96/month that we weren't spending in 2006. That is some significant cash.