I think a week of parking would run 300 CHF...What about rent-a-rentner, or a man with a van type setup? A family friend of ours (not anywhere near you, unfortunately) drives people to doc appointments and such for a fee per km. Might be cheaper. Do look into the park-n-fly options in Oerlikon, and even consider one-way car rentals. Hope you find something that works and doesn't break the bank.