Take on the presidential memoir

As Barack Obama's memoir breaks records, it begs the question of Trump will have a memoir and if so, who will write it for him. We all know that Trump will likely move a lot of copies even if he has to get the GOP to buy them like they did for Junior's book and also know that if a Trump is involved it will be self serving but mostly we wonder if it can be longer than about 20 pages as by that time Trump will be bored.
Anyway, it's also interesting to see if it can be published from prison