Does anyone have a system for keeping track of when someone owes you a small amount of money? It comes up when you split something with someone, but only one of you pays and the other doesn't have cash. For example, I split a pitcher of beer with my friend and he didn't have the cash to pay me back right away.
I'm thinking of keeping a Google spreadsheet on my phone. Additionally, I'm thinking of setting a maximum I could be owed at any time, for example $20. That means, if four people owe me $5 and someone else asks if they could have $2 for parking, I'd say no. What do others think?
Of course there's been times I lend a person money and realize I'm not getting it back (either because they moved away or I now know they're unreliable). I'm thinking there should be an element of time to my formula.