In the past, I have always only charged for the entire project all at once instead of by the hour.
Main trick to mitigating feature crap I have used is by first I add extra padding to cost.
Second i tell my clients that I provide free maintenance for 2 weeks after the project si delivered. Mostly this helps because clients want speed over reliability. So we push and the next two weeks is bug fixing - sometimes it's three.
However no matter what happens I would never build a new feature in the maintenance period
I get it. Google wants their own Yammer, am I right? That's interesting because I am not sure how many tools would we want to switch context as employees.
You could lose the piece of paper making all your passwords vulnerable. My colleague stored all passwords on a note in the phone and lost the phone on vacation.
I had to change all the passwords immediately because of this. Even if i have 1Password on the lost phone, i don't see how anyone could get inside of it
Such simple mechanism.