For CD in your trailer you might look into automobile type radios with CD playing abilities. The operate on 12V. If you already have a car type radio in trailer with cassette tape ability you can get a portable CD player that will play thru the cassette section. Mine was about $75.00. A boom box is not a bad idea but try to find one that operates on 110V and 12V. Batteries don't last long playing CD's. Of course if you want to get really elaborate get a CD box that will hold 25 or more CD's. There are some built for cars . Check with with an auto audio specialty store.

Roy