A $35,000 fibreglass cabin cruiser appears to have been deliberately torched in Seaford early on Friday 14 October.
Police are investigating the blaze which broke out at 2am in the garden of the Seaford Grove property.
A crime scene guard was established around the remains of the 6.2 metre Savage half-cabin boat sitting on its trailer and an arson chemist was called in.
A neighbour woke the 45-year-old owner and alerted him to the fire.
Their attempts to douse the flames proved fruitless.
Anyone with information should call Detective Senior Constable Richard Brown, Frankston CIU, 9784 5555.
