A reward of £30,000 is being offered by Cheshire Police for information that leads to the conviction of the person that stabbed and strangled a 40-year-old man in his own home.
Carl Chadwick was found dead at his home in Grasmere Avenue, Warrington, on 29 January.
Police also believe several thousands of pounds of cash were stolen from the flat following his death.
Mr Chadwick's family appealed to anyone with information to come forward.
'Liked in community'
His cousin Lisa McQuillan said: "Carl was such a lovely man who wouldn't harm a fly. To have him taken from us in such a violent way is heartbreaking.
"We know he was well known and liked in the community and I want to appeal to all the people who knew him to think carefully about any information you may have heard or know. Even if you don't think it is relevant, please just tell the police and let them decide.
"No one deserves to die the way Carl did but the only thing we can do for him now is make sure whoever did this is caught and punished."
Mr Chadwick was last seen in a local shop on 18 January.
Police believe he died within a few days of that sighting and they have urged anyone who may have seen him after that to contact police.
Det Insp Nigel Wenham, of Cheshire Police, said he believed someone in the community knew who was responsible for the murder.
"The offer of this substantial reward may motivate someone to speak to me or bring forward more information from people who have, for whatever reason, not felt able to talk with police so far," he added.
A man, 32, and woman, 29, were arrested on suspicion of murder and have been bailed until 8 March.