[konne88]

I personally used to keep about a $20K balance in my checking account, and I was actually surprised by how much a difference it can make to invest that. If you have an investment with an expected annual return of 5%, that's a $1K / year that you are missing out on.

We've also seen users who needed to keep much larger amounts of money in their account for relatively long periods of time, because they were shopping around for a house or trying to buy a new car.