Staged Readings are great, because pre-production is short and sweet.
It is basically a complete show, with basic blocking, some basic audio (optional), some basic lighting (optional), some basic set (optional), some basic costumes (optional), and the actors don't need to learn their lines.
Staged readings often occur with new works to "try it out" on a small audience. Most staged readings I have been involved in have had 3 days or less of rehearsals and between 2 and 4 days of show, and are often in a black box theatre.