What an interesting place to work! Congradulations!
Here is the quick and skinny. Everything is very overpriced as far as rent (we are talking from $600 one bedroom being cheap to about $2000 and up for a one bedroom getting expensive around here). It does get somewhat cheaper the farther out you move but you have to deal with the other ten thousand people all heading in the same direction you are at the same time. Both Alexandria and Fairfax county are expensive, but schools are better. Those are both in Virginia. In Maryland you have Prince Georges (where I live) and Montgomery counties. Prince Georges has a lower cost of living but we also have worse schools and higher murder rates (than even DC!). Montgomery county is also expensive but schools are better there.
DC itself is a mix of everything. There are some cheaper housing options there but also there are more expensive options too.
Driving in the city can be a nightmare, potholes galore, everyone is in a hurry. The Beltway (I-495) can be one of the most frightening but I would say I prefer that to driving in the city. If you wern't an aggressive driver before, you might become one.
The great thing about DC is that there is so much to see and learn. There are so many good nursing schools right around here as well if you want to further your education.
If you have any other questions just let me know