An auction for a home-made, Interisland amphibious van has reached $5000, with 118 bids on Trade Me.

The matt black DIY boatvan, called Roofliss by its builders Adam Turnbull and Dan Melling, captured public imagination when the two aeronautical machinists used it to cross the Cook Strait in 10 hours at the weekend.

The pair, both 23, dreamed up the interisland voyage to keep busy and out of Blenheim's bars. They completed the conversion of the Toyota Townace for about $2000.

Their auction description attested to the power of the "only van you can't get done DIC in".

"This van is so rad, it once got a girl pregnant just from looking at it...Good for a spot of fishing. Marlins practically jump onboard, with the groupies."

Starting with a $1 reserve, the instant celebrities said they were willing to swap their "Loveboatvan" for "all sorts of stuff except Sealegs which aren't proper amphibious cars really are they? Just an expensive dinghy".

The auction was up to $5350 at 9am today.

In the dozens of questions from tyre-kickers, well-wishers and the curious, the two said they made the voyage on about $40 worth of gas.

The van is now in Auckland, where it was "doing the rounds", they said.

Bids close on September 14.