We ended up getting a lot of cash by pure dumb luck. The easiest way to get more cash is to register for less gifts.... which we unknowingly did. We thought we registered for a ton of gifts but they all got bought up quickly.
We got 14K cash just because we ran out of things to register for.... Then again, with our two big families we invited 425 people. So that might have affected it out of sheer volume. Oh, and greeks are like Jewish people, they like to show off with the size of their gift. We got a few sizeable checks just from generous family friends.