You can sometimes get a bargain at some of the expensive hotels. I once got a room at the Sofitel under the half-price hotel plan from Travellers's Advantage (same as Entertainment). Last month, I stayed at the Marriott for 256Sfr/night ($167) for 2 people, including breakfast. In two weeks, I will stay in nearby (and less popular) Baden for 195 Sfr /night at a Best Western.

I've stayed at these hotels in Zurich, all of which I can recommend. All are in the 200-300 Sfr range: Marriott, Sofitel, Central Zurich, Schwiezerhof (all by the main station), Movenpick & Rennissance (by the airport).

There is an Ibis hotel on Zurichstrasse that should be a lot cheaper. I haven't stayed at that one, but I have stayed at other Ibis hotels that seem OK. (Ibis is owned by the same people who own Motel 6).