"Quick, we need an opener that's quick, easy, and really barbershoppy!"
A classic chart by the late, great Walter Latzko, "Hi Neighbor" can be done quickly, is an easy song to pick up (especially with a Tim Waurick learning track), and starts a set off right. (Listen to The Bluegrass Student Union's Legacy album for a sense of the fun it promises.) It's one of those arrangements that needs to be in your back pocket, a "we could roll outta bed and sing this" kind of song.