Group houses, my friend. Though I never did that big house in Dewey thing in my 20s (could not see being in a house with 20 people and 10 beds, even back then). I headed to Rehoboth the first time just a few years ago and when you're getting a house with a large group, it's probably less than the motel. I also have a group of friends who've gotten houses together out at Deep Creek Lake each September. Cheaper than a hotel 'cuz it's after Labor Day and you get a big ole house for the 8-10 of you...great times, I recommend it.
PS, boomboxes work at a motel just as well as in a living room or on a porch! (Though I wouldn't be taking that Bose SoundDock to the beach; don't think it can run on batteries anyway...)