The 30 McLaren sports cars and their owners are on a road trip from Auckland to Queenstown.
Richard Jeans, of Wana Clean, said he had never had the pleasure of grooming a McLaren before, and was more used to cleaning Prados and Lexuses.
He and his crew were giving the cars an exterior wash and wax and an interior "vac and wipe".
One of the convoy, a 1994 McLaren F1, is capable of almost 400kmh and is said to be worth about $20million.
The cars were manufactured by McLaren Automotive, in Surrey, England, founded by legendary New Zealand racing car driver and designer Bruce McLaren, who died in 1970.
It was a McLaren that British comedian Rowan Atkinson famously crashed in 2011, his insurance company dishing out around $2million for repairs.
Two cars are understood to have dropped out of the convoy since leaving Auckland, but not through any mishaps.
The cars have been travelling at the speed limit on the way south but today will be taken for a spin around Cromwell’s racetrack at speeds well above that.
The cars, some of which have been shipped from overseas for the tour, are due to leave Wanaka early this morning.