Hope you worked this out, but in case not, I can recommend staying in/around the Bowie, MD area off Rt. 50. Prices will be less and easy access to Rt. 50 which is the main
route into Annapolis. I am from there, so know the area pretty well. Annapolis is expensive, but I have had luck on Priceline in the name your own
price area and was able to book a 3 star hotel for $50 once.
Good luck.
cj