Either ditch the car or store it in a garage outside the city for trips you take that are not convenient by rail. You do not need it for daily use. Get rid of the idea of commuting by car entirely.
Start looking for direct lines to midtown. Forest Hills has some really nice places and the walk to the F is not that long. The trip in will also be quick around, I think, 42nd street? (I will have to look at a map... www.onnyturf.com
has a good scale subway map).
I am in Hoboken now, and there are spots available for much less than NYC (most expensive was somewhere around $225 I believe). Rents on some buildings, more likely onthe older ones, are controlled and can be questioned by City Hall. The Path is quick to Midtown @ 33rd and 6th, the Ferry is so-so (and expensive) and there is the 126 bus that goes into Port Authority (42nd and 8th avenue).
Jersey City has some nice places as well.
If you do not have a shore house, and do not have relatives close by, and do not have a classic 70's Vette, I would think VERY strongly about selling the car. Zip car may be more expensive per day, but when you look at the bottom line, it comes out surprisingly in its favor (OMG $70 a day for a car? I don't want to spend that much for a day at the shore/CostCo trip/whatever... wait a sec, if I pay $100 a year in insurance, and $300 a month in parking, thats $4600 = 65 trips!!!!! More than once a week, for the whole day........)
Anyway, NYC CAN be very expensive, but itcan be less expensive so long as you know where to shop and do not spend too much time OUT in it!