Nadine Garvie, 36, forced her way into 72-year-old Brian Williamson’s Jedburgh property after she had been made homeless and pushed him onto a sofa.
She then searched his pockets and found £50 in cash, which she took off him.
Prosecutor Fraser Matheson told Jedburgh Sheriff Court: “As she was leaving she was laughing and waved the cash at him. The man got on his mobility scooter and went to a friend's house who contacted the police.”
Garvie, of Forthill Terrace, Jedburgh, pleaded guilty to a charge of assault and robbery on January 9 last year and received a 10-month jail sentence.
She also received another six months by taking £300 from Mr Williamson's bank account after he had given her his card and PIN number to buy items for him in September 2019, and later that day using the card to get a total of £450 in cash back from three shops in Hawick.
Garvie also pleaded guilty to theft of a bank card, mobile phone and house key from another man's home in Kelso in October 2019.
She is currently serving a prison sentence for spitting in a police officer's face at Perth Police Station and then repeatedly claiming she was infected with hepatitis C and is not due to be released until May 21.
Sheriff Peter Paterson imposed jail sentences totalling 16 months saying "she had taken advantage in a fairly direct and cynical manner of a man aged 72 with difficulties" and added the sentence would start on the expiry of her current jail term on May 21.
Last year, Garvie received a 16-month sentence for spitting twice in the face of a shop assistant claiming she had cornoavirus.
The female worker had challenged Garvie as she tried to steal chocolate bars from the Spar store in Selkirk.