Can sequencer music sound like real instruments?

I used to be a lead singer and rhythm guitar player in a band. I am interested in getting a one man gig on a cruise ship and play and sing along with a sequencer or prerecorded accompaniment. I've seen other guys do this on cruises and several of them were pretty bad so I think, with enough practice I can put together an acceptable show. I have very little knowledge of sequencers. Is there a setup that is not terribly expensive that produces sounds like real instruments? The midi files I've heard online sound really cheesy. I can get a piano player to help if needed since these machines seem to require piano ability to program. Any advice or suggestions are appreciated. Thanks from the "future cruise entertainer :-)"