Officers found the victim with severe head injuries on the morning of December 30th after the suspect telephoned cantonal police.
The 29-year-old son of the family that owns the home was arrested and has “basically admitted” to killing the man, 20 Minuten newspaper reported on Monday, citing the local prosecutor, Alexander Knauss.
“He is now in custody and was moved to another prison,” Knauss is quoted as telling the newspaper.
The prosecution said the exact circumstances of the death remain unknown and its is unclear why the victim and the son were staying at the villa.
The rest of the family were reportedly on holiday in the canton of Graubünden.
No motive has yet been established, said Knauss, who added though that the two men were friends.
There were no initial indications that a “romantic relationship” existed between the two men, he said.
The suspect managed his own art gallery for several years, exhibiting the works of such well-known artists as Andy Warhol, 20 Minuten said.
“I am shocked — he was always highly respectable and charming,” a woman who grew up with the alleged assailant told the newspaper.
The man’s family is not commenting publicly on the case.