I wouldn't leave a bike locked up in NYC anywhere, for any price, without the thought that it will be stolen. With that in mind I bought a $135 Trek 7000 (old mtb style, not the newer upright bike) on ebay and use that as my commuter, mostly stock except the tires. I leave that bike locked up anywhere I need and don't worry about it, except that the lock costs almost as much as the bike. But, since I have indoor parking at my office, I don't hesitate to ride my $4k carbon fiber bike in on occasion.