Replying to Wanaka - Queestown

I will be in Wanaka and one morning at 8:25 I need to catch a plane back at Queenstown airport...

what would be the best way to go about this?

is there a way to travel from Wanaka to Queenstown in the evening? so NOT 5 pm like the shuttle services but evening 8pm or some shit.
How much is a taxi from Wanaka to Queenstown airport u reckon?
Or is there a company that will let me rent a car in Wanaka and drop it off at the airport.....

oh, and do they take VISA down there?