Work In the DC metro area.
How is your commute? Where In St. Mary's county do you live? Where in the DC metro area do you live? What time do you leave in the morning? I'm playing with the idea of moving south (currently in N.Beach) for the cheaper cost of living. Thanks!
I live in Charlotte Hall and commuted between here and Bethesda (63 miles), Washington (about 40 miles) and finally Arlington (about 45 miles) until retiring last year. I drove to Bethesda and although it was a haul, I got used to it. However it did increase the wear and tear on my car and me! When I changed jobs and worked in DC I joined a car pool for a while and also caught the commuter bus in Charlotte Hall. The car pool was fine and the bus wasn't too bad other than it took forever and there was the issue of planning for schedule changes. The last few years I worked in Arlington and drove most of the time. The one thing I will say is the commute played a part in my decision to retire. The quality of life issue was big with me and I was always tired after working a long day and what was sometimes a 2+ hour commute. The only good thing was that by the time I got home I usually had decompressed from any work issues.
My departure time varied and I was fortunate to work for agencies and/or supervisors who were very understanding when I had to leave early to attend my kid's various after school and other activities. I found that leaving a little later was better (after 8:00 a.m.) but that changed a bit toward the end of my career. Leaving very early (5:00 a.m.) worked too.
As far as cheaper cost of living...not sure about that. As others have pointed out, your longer commute time is costly in terms of fuel, wear and tear and your (irreplaceable) time spent commuting. You may be able to get more house for the dollars but I've been here for 20+ years and haven't really paid that much attention to the local housing market.
All in all the benefits of raising a family here, having a few acres of land and the relative safety of St. Mary's made the sacrifices well worth the inconvenience of the commute. I agree with your plan of purchasing a disposable car however, I would suggest that you make sure you get a comfortable car. Nothing makes a long commute worse than getting out of your car in pain!
Good luck!