Hi just remembered who we used,First step rentals,lovely clean modern home with 3 beds,near Marion so near the city and beach with internet. $700 a week
We are staying here:
Its right in the city centre :)
We are in a studio but they also have two bedded apartments x
Try this place also, lots of new arrivals to Adelaide have stayed there:
Between bus stops 1 and 2 into the city and you can also walk across the parklands into the city. Great location.