Real talk, my mom plays bass. We fit that, two adults, two kids, a pair of fiddles and backpacks for a weekend away: all into a Geo Metro. The trick is to put

Real talk, my mom plays bass. We fit that, two adults, two kids, a pair of fiddles and backpacks for a weekend away: all into a Geo Metro. The trick is to put the neck down between the drivers with the rear seats folded down, and then fold them up. Wasn't terribly comfortable back there, but we were small enough to deal with it. Oh. You edited your post to say "decent safety requirements". A '91 Metro probably doesn't fulfil that these days. But they'd probably do fine with an electric conversion.