Stay in the city is literally 10 mins from airport accommodation is cheaper in the wet season that's from now on. Mitchell St is the hot spot great night life and cheap rooms you will have to search the web lots of backpacker rooms there. Enjoy about 6 years ago
There is a Rydges Darwin Airport hotel which provides a shuttle service.
Its clean and close to the airport, suitable for late arrivals or early departures. They have a swimming pool, cafe, restaurant etc so if you don't plan on exploring the town, this is an ideal overnighter.
I've stayed here overnight transiting between Sydney and Timor Leste. almost 6 years ago