Damion Barton, of Conyers, pleaded guilty to holding Eva Francis, 61, against her will, murdering her and robbing her family in September of 2010.
His guilty plea spared him from getting the death penalty, according to the Atlanta Journal Constitution.
Barton lived with Francis and her husband, Errol, for four months. His mother had been close friends with Francis for years, and the couple was attempting to help him get back on his feet after he moved to Snellville from Ft. Lauderdale, Fla.
Barton, 33, had allegedly used the family's vehicle without permission, which resulted in the couple kicking him out. Prior to that, Errol had planned on making him a business partner.
Errol was away on a business trip at the time of the murder, and called police when his wife failed to answer the phone.
According to Gwinnett County Police, Francis was found "sitting on the master bedroom floor in a nightgown, her ankles and arms bound with a telephone cord and her mouth covered with masking tape."
She had gunshot wounds to her thigh, upper leg, chest, abdomen and face, according to the Gwinnett Daily Post.
Barton was sentenced to life plus 20 years.