The ibis Budget at SYDd airport has lifts and is a bit of a slightly higher standard than the ibis Budget MEL airport.
If you are like me, HLO, the ibis Budget MEL is great, if all you need is a place to be, ie have to be at MEL airport for an early am flight out, where you can just drop the room key into the box.
Hours of operation at the ibis Budget MEL airport is also limited, as after 22.30, you have to use your credit card to do the checkin, the staff might be there till 23.00, but those 2 are the only 2 downsides for travellers wanting ibis Budget rates at MEL airport, (1) not good if you have many bags, and (2), if your arrival time is the last flight of the night/early am. O, not forgetting the noisy aircond.
Other than those, its the cheapest spot at MEL airport within walking distance of the terminals.