Plus a good amount of technical know-how and ops work, which is only free if you're a hobbyist building a proof of concept. If you're the actual NYPD and you want it to work accurately and reliably in prod, you need budget for either in-house tech talent or a company that will do it for you.
>>geofft+(OP)
True. A city near me paid about $350k for a few dozen ALPR cameras at major intersections. Not a bad price for near total surveillance of every vehicle traveling in and out of town