Thomas Rutledge, who was 51, was found by police after neighbours reported an attempted break-in at his terraced home in Fletchers Mews, Neath Hill in January.
His body was so decomposed that experts could not work out the exact cause of death, but hypothermia or pneumonia could not be ruled out, the inquest heard.
Coroner Tom Osborne ruled the death was due to natural causes.
Mr Rutledge, who had schizophrenia, lived a “lonely and troubled life” and had little contact with his family, the inquest was told.
He was known to be a hoarder, and MK Council had placed a closure order on his house due to anti-social behaviour problems with visitors who neighbours believed were drug dealers.
A council notice taped to the window months before his death stated that “regular” police patrols would visit the premises.
Ayman committed suicide in his Ashland flat but his body was not discovered until up to nine months later.