It happened around 3:15 p.m. Monday in the 1100 block of N. Lincoln Street in Wilmington, Delaware.
The resident, an 87-year-old woman, came to the door to find a man who identified himself as being from the water company. Police say he flashed a card, but it was too quick for the woman to read.
The victim said she was told there was something wrong he needed to fix, and if it wasn't checked out immediately her bill would be more than $200.
She allowed the man to enter the home, at which point he turned on the faucet and began asking if anyone else was home.
At that point the woman told the man to leave, which he did.
The suspect is described as a Hispanic man in his mid 30's. He was about five feet tall with light skin.