Olga Rutterschmidt, 75, and Helen Golay, 77, are said to have taken out policies on two men before running them over in cars.
They received $2.8m (£1.4m) in payouts, prosecutors told LA superior court.
The pair deny charges of murder and conspiracy in the deaths of Kenneth McDavid and Paul Vados.
They face life in prison without the possibility of parole if convicted of murder.
Mr McDavid, 50, was found dead in the Westwood area of Los Angeles in June 2005. Mr Vados, 73, died in Hollywood in 1999.
| || They made a profit on the lives of men who were homeless and destitute |
Deputy district attorney Truc Do
Deputy district attorney Truc Do told the jury: "The victim would always be run over - crushed to death - in an alley with no witnesses... it always looked like it was a hit-and-run accident."
He said the women had found the men in a homeless shelter at a Hollywood church, provided them with apartments and supported them for two years - while taking out multiple life insurance policies on them.
Mr Do said the two-year timescale was important, as it was the length of time it would take to make the insurance policies incontestable.
Mr Do said the men were "forgotten" people, so no relatives were likely to come forward to contest the insurance policies taken out by Ms Golay and Ms Rutterschmidt.
"They made a profit on the lives of men who were homeless and destitute," he said
Prosecutors played jurors excerpts from a secretly recorded conversation between the two women shortly after their arrest.
Ms Rutterschmidt is heard telling Ms Golay: "You were greedy. That's the problem."
Ms Golay replies: "Be quiet. Don't say anything."
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Published: 2008/03/19 11:38:43 GMT
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