If u knew how to find someone who had dropped their wallet, which amount of cash in the wallet would make u more likely to return it?

I've returned every wallet I've ever found. Once, I found one belonging to an 18-year old woman while out walking. I returned it to her house on my walk and her father answered the door. Turns out the wallet was stolen from his daughter a couple days before in a robbery in which she was beaten to the point of hospitalization. She had just been released from the hospital. They were thankful for the return of the wallet, credit cards, ID, etc.

Cash makes no difference in the rate of return. Return it always.