Short review: (Only Life together, I haven't read Prayerbook of the Bible yet). I have read this a couple times in the past. This time his comments on the expectations of community and living in the community that God has placed you in were the sections that most struck me. This is a short book and if you have not read it yet, you really need to.
Full review on my blog at http://bookwi.se/life-together-bonhoeffer/