A BACK FENCE CHOIR script links about 20 songs into a show, with a simple storyline.  A plot synopsis is on this site, and the first few pages of the script. 

The show would be:

inexpensive. Needs one minimal set (or none) and 6 characters (or fewer).  

simple.  The very basic story centers on love. A couple finds commitment, with (and sometimes despite) their friends' help. 

flexible. With over 40 songs to draw on, the show can be modified, depending on venue and intended audience.