A passer-by noticed a bad smell and flies around the vehicle at the branch on Longman Road and she contacted police at 3:30pm on Monday.
Officers sealed off the area and are understood to have found the body in a campervan with a mattress in the back. The death is not believed to be suspicious.
The area was cordoned off while forensic officers were on the scene. It is understood the vehicle was moved around six hours later. Car park operators Total Parking Solutions said they did not have staff on site and had not been alerted to the vehicle.
Police revealed yesterday they were not searching for anyone in connection with the death of the man. While formal identification has yet to take place, it is not understood the man is a missing person and not believed to be local.
A police spokesman said: “The death is currently being treated as non-suspicious, although a report has been submitted to the procurator fiscal and a post-mortem examination is awaited.”
An eyewitness to the unfolding events, Graeme Cormack, owner of Hannah’s Krazy Kitchen – a burger van in the car park – said: “I just saw the police and B&Q staff at the vehicle.
“About 3:30pm, I saw a police car and a van all at the other end of the car park. I left about 4pm and the area was all cordoned off. I have been here six years and I have never seen anything like this before.”
Councillors were shocked by the news, with Inverness South councillor Andrew Jarvie saying: “No matter the circumstances, it must be a very difficult time for the family.
“I hope they get some sense of closure through whatever investigation is ongoing. It really shocked me when I saw that this happened.”
Cllr Ian Brown added: “I’m surprised that B&Q themselves didn’t notice there was a car abandoned in the car park for any length of time.”
The car park is managed by B&Q, while the administrators for car park fines are Total Parking Solutions, whose spokesman explained: “We are not on site – parking tickets is a function carried out by B&Q themselves.
“If people are issued with a ticket, which they should be after three hours, and the ticket is not paid or the car is left for a longer period of time, we would remove the car.” A spokeswoman for B&Q declined to comment, saying the incident was a police matter.