Sam moves into a nursing home.  As he looks over the list of citizens 
living there, he realizes there are 3 times as many women as men.  He 
decides this is a good time to make so money, so he posts a sign on his 
door.  SEX FOR SALE.  

The first night he has a knock on the door.

Sadie says, "What does your sign mean?"

Sam replies "I am selling sex."

"Well," says Sadie, "How much?"

Sam thinks slowly and replies, "I hadn't thought much about prices, but
I suppose it will be $5.00 on the floor, $10.00 on the chair, $15.00
standing up, and $20.00 on the bed."  

Sam is quite relieved when he sees Sadie reach in her purse and pulls
out a twenty dollar bill.  "Oh, you want it on the bed."

"No," says Sadie, "4 on the floor!"