You can also try Country Inn and Suites. They are below the price point for Holiday Inn Express and Hampton Inns. I do an overnight between Maryland and Disney and usually stay at the one in Florence, South Carolina which was recently renovated.
There is a fairly new one in Fredericksburg, Va which is about an hour south of the DC beltway. They are cheaper in the Richmond, Va area depending on how far you want to drive.
There are lots of less expensive places but I've only tried the ones mentioned so far.
You can also go to trip advisor website and put in the town you are considering and see what comes up ranked in the top 1-5 places. Read the reviews.