Ronald Smith was found at the foot of his stairs a month after the alleged attack at his maisonette in Cottage Walk, West Bromwich. He had been knifed up to 27 times.
The 65-year-old was described as a private, slightly eccentric man who was careful with his money and would not open his door to strangers, Wolverhampton Crown Court heard.
His sister Doreen Smith described him as a 'kind, generous' man who liked to live a 'quiet, normal life.'
She said Colin Cooke senior, aged 62, one of the two defendants, was a friend of her late brother's and had been fishing with him.
Cooke's son, Paul Cooke, a prolific burglar, was jailed for more than 28 years last year after admitting killing Mr Smith in May 2015.
But it is claimed he was not alone that night and that his father and brother, 37-year-old Colin Cooke junior, may have been with him.
The prosecution says Cooke senior persuaded Mr Smith to open his front door to the robbers and with his son harboured Paul Cooke after the murder by arranging accommodation for him.
Neighbour Lillian Costings said she heard two or three voices 'shouting' in Mr Smith's flat on the night he died and also heard banging, 'as if someone had knocked against a cupboard'.
She said it was 'very unusual' given Mr Smith's quiet lifestyle.
Neighbour Michael Sutton also heard shouting coming from the flat. He told the court: "I could hear loud voices, it sounded like there were maybe three voices."
Colin Cooke senior, from Wilford Road, West Bromwich, and junior, of no fixed address, deny conspiracy to rob Ronald Smith and assisting an offender.
The case continues.