I hate to be a bummer, but the long term parking situation at BWI is abysmal. The first time we used the long term economy parking lot, we waited 1.5 hours at 2am for a shuttle bus to it (our plane was delayed around 5 hours). Although it was infuriating watching all of the other shuttles go by but no green lot bus, I guess we could KIND of understand it given the hour. Eventually a police officer had to do something as another family who was waiting with us had their exhausted very young children with them and the father was about to go ballistic.
The second time we tried the long term economy parking lot, we once again had a ridiculous wait at the terminal for a bus to bring us back to the lot. 45 minutes later a bus finally arrived, but not until my husband started bugging the driver of every other bus that came by to radio in and ask for them to send a bus to pick us up. We shared a stop with the Amtrak bus, the express lot bus and several others. There are two economy lots... one is blue and one is green. Blue has been full the two times we went there, but the bus service from green is awful. We saw 6 blue busses stop at our stop before a green finally arrived.
Of course, the green was packed because everyone at all of the other stops at the terminal had ALSO been waiting 45 minutes for a bus, but we crammed ourselves on there and stood, afraid of how long it would take another bus to come. When the bus was dropping us off and not picking up other passengers, the people waiting for a bus were absolutely FURIOUS so I guess they had been waiting just as long for a bus.
When we got home, my husband called the BWI parking line that we wrote down from a poster that said "tell us how to serve you better" to complain about the horrible wait time we had both times we used their economy lot. They apologized and when he asked what they were doing about it he said that they were aware of the problem (got many many complaints daily) and had recently called a meeting about it but could not think of a way to remedy the problem. So, there you have it.
There is ALSO an express lot there that i believe is $11/day. It's still kind of "out there" and requires shuttle access but both times we saw the express shuttles (which are much smaller, kind of mini coach busses, but run much more frequently) come by every 5 minutes at MOST. Next time we fly out of BWI if we don't do towncar service (which we do if we are going away for 2 weeks or more) we will probably try the express lot. THe extra few $$/day seems worth it for the difference in service.
We have done the park and fly through a hotel thing at dulles (not at BWI yet, the timing never works out for us) and it worked out GREAT. The hotels are very prompt about picking up their customers.
All of this is a rant against the long term economy parking lot at BWI which has problems because it is the largest. BWI itself is just fine to fly out of. Security is tight but they are professional and efficient and I haven't seen very long lines... they quickly pull people who are flagged for further screening out of the way. Even when you are flagged for further screening, they are fairly quick and efficient about it.
Lisa