2015 Ameri-Lite 248BH

Just purchased new Gulf Stream Ameri-Lite 248BH (Ultra-Lite) TT.....any thoughts? Would like to use 115-volt home stereo FM receiver/cd player/dvd player/speakers. Am wondering what type outside antenna to use, since have read that the aluminum siding on TT will shield an inside FM antenna..

Prior TT, 2010 KZ Sportsmen Classic 14RK, with no cooktop, furnace or water heater, but has 5K BTU side-mounted AC. (Now on sale consignment with original dealer.)