How Much Would It Take

On the way in to work this morning, I noticed a sign posted on the door:

Found some money. If you can tell me the EXACT AMOUNT it will be returned.

Followed by a name and phone number.

This got me to wondering. How much money would I have to find to bother with a sign like this? Now I am the type of person who will correct a clerk at the checkout line when she hands me too much change. In that situation it really doesn't matter the amount, I have given back amounts ranging from just a quarter to a ten dollar bill.

But if I find some laying on the floor at work? What would it take in that situation? A couple of bucks??... Probably not...it's just not enough to bother about. But what about $10? $20? $50?

I don't know. Thoughts?