The Formule 1 is set in the beautiful industrial landscape with a Maccas and KFC nearby. What more could you possibly want???

The cheapest single rooms I have seen are on this site.. Haven't stayed there though so can't tell you if they live up to their web images.

there are two good little motels/ b&bs die-by-side along the pacific highway at artarmon, just before chatswood (near where epping rd meets the pacific highway). from memory last time I drove past (9 months ago) they were offering doubles for less than A$50.
I think one of them might be called the "artarmon inn" and the other the "shore inn".
I doubt they have websites, but you could check the yellowpages (online) for their phone numbers
easy enough to get into the city by bus from there