The cheapest person I knew was my maternal grandfather. He raised 5 children during the Great Depression on a teacher's salary, on top of which he loved math. My mother tells me stories of cabbage, franks and potatoes for dinner for days on end, also baked beans. Grandpa kept track of every penny he had, and every penny had to be accounted for.
One glimpse I had of Grandpa before I was born is the story told me by mymother's college roommate, who later became her sister-in-law. The roommate was walking with Grandpa down the sidewalk. They came to the street crossing and started to cross. In the middle of the street was a dime, and Grandpa bent down and picked it up. He stood there, seemingly frozen.
The roommate asked him, "What's the matter"
Grandpa answered, "Well, I found a dime, and I don't know what to do with it."
"Why don't you put it in your pocket?"
"I can't. I know exactly what I have in my pocket, 'cause I took it out of my savings and accounted for all of it, and this dime would just foul up my books."
"Well, why don't you give it to me then?"
"Well, I can't do that. I'm the one who found it."
This was still in the middle of the street, and cars started veering around the young lady and the older man in the middle of the street. Some made gestures at the couple. Grandpa was oblivious to them.
The roommate thought a bit, then, taking a chance, made up a little white lie, to get them out of the middle of the street. She said "Hey, don't you remember that phone call you made (This was during the time when phone calls cost a dime) and I'm not sure, but did you remember to write down that you spent a dime? If you did, then you can put that dime into your pocket, you'll break even, and you'll have the same amount of money as before."
"'Fraid I don't remember that".
"I do, really. Trust me. And I don't think that after the phone call you took out a book to account for the dime you spent making the call."
"Are you sure"
"Absolutely".
"OK". Grandpa was satisfied with this. They crossed to the other side of the street and all was well.