How's this for Kiwi ingenuity:

You dig a shabby old caravan out of a paddock and strap an outboard motor on the back. You put some polystyrene on the bottom so it floats. You slap on a lick of paint.

Then you take it out to catch some fish.

That's what a group of lads from Waiuku, south Auckland, have done. Their caravan-cum-boat has taken the Kiwi number-eight wire mentality to a new level.

The vessel boasts an impressive top speed of 15 knots, and can be launched from the back of a car. You steer it from a wheel set into the central table.

The lads found the caravan rotting in a paddock, with long grass growing through it the inside coated in chicken droppings.

"We thought: that's us. That's it, that's what we'll do," Darin Burns, one of the builders, told TVNZ.

A mechanic by trade, Burns put his grease-monkey skills to the test alongside his mates to get the caravan seaworthy. It took them six weeks to ready the vessel.

"It's just testing yourself, mainly testing yourself and seeing what you can come up with, something a bit different," Burns said.

"We get a few funny comments, eh. A few looks. They don't know what's going on."

His mate Mathew Douglas, a fitter and welder, reckons their seagoing caravan is safer than its land-based cousins.

"We haven't got the issue of a puncture," he told TVNZ's Seven Sharp.

Last year the same group of mates made headlines when they converted a Subaru Impreza into an amphibious vehicle. They eventually sold it on Trade Me for $3000.

Burns thinks the caravan is an improvement.

"[The Impreza] was neat, but I think I prefer the caravan in the way of room, fishing, and you just hook it on and go."

They are planning another outrageous vessel for next year.