Does anyone definitively know Part 107 rules in New York City? I'm looking at the sectional chart and it shows that Lower Manhattan and the DUMBO area are in Class G airspace. Parts of the Hudson River are in a special flight restricted area but I can't see any notes on height limits.

I've also read that hobbyists are not allowed to fly in most of Manhattan, how would they know if you're a commercial operator or hobbyist?  Do FAA Part 107 holders fall under FAA/national jurisdiction and hobbyists fall under the local NYC jurisdiction?  Thanks.

That place is a nightmare to get in and out of for manned aircraft, can't imagine it would be any better or easier for UAVs.
You need to contact the local TRACON/Approach Control for the area to find out what the FAA side has to say about P107 ops in the area.  My guess there is they'll tell you to stay below 400 feet and away from all airfields and their approach and departure paths.  I'd see you playing hell to get clearance in those areas considering how busy they are.
Now as to NYC flight ops, that's a horse of a different color.  If you know anything about the city helo ops and who controls them then I'd contact them to see what they say about UAV ops.  My guess here is the helos operate on a see and avoid bases and use set corridors for transit.  There may be a city agency that controls this stuff but I couldn't tell you what that is.  It is a big brother city with lots of government and associated bureaucracy so I'd be prepared to be bounced from one agency to the next over any attempt to coordinate your flight business.  You could also check with the local screen actors guild to see how they coordinate flight ops for doing filming and the like in the city.  Bottom-line, your Part 107 does not give you a blank check to fly in airspace that is busy, you will still need to get clearance and permits.  Maybe someone here in the forum who has actually done work there would know enough to provide you with some insight.
Good Luck

Last time i heard, NYPD is banning drone from Manhattan and ask people who spot it to report it to them.
I tried flying it in Brooklyn (bushwick and near Prospect park) once. Put notice on, but still see planes flying low. Roosevelt Ave seems to be safer, but be careful with chopper around and not flying it within the monument ( i asked and they said no).

fans1aa14a1b Posted at 2017-9-10 16:55
Last time i heard, NYPD is banning drone from Manhattan and ask people who spot it to report it to them.
I tried flying it in Brooklyn (bushwick and near Prospect park) once. Put notice on, but still see planes flying low. Roosevelt Ave seems to be safer, but be careful with chopper around and not flying it within the monument ( i asked and they said no).

That is too bad...I see it being a real challenge in that area, sadly.
What about Central Park, is it a problem there?  What have past RC aircraft flyers done to fly there, can't imagine they had to go outside the city to do so, but maybe they did.
Of course we are talking about hobby ops, the question was about P107 which I assume means operating commercially and that is a whole other problem there.

You might want to download an app that can provide you with updated sectionals.  There are a few out there.  I use UAS107 (https://play.google.com/store/ap ... nrobotix.labs&hl=en) .  It's a Part 107 prep exam app, but it also has a dynamic sectional chart viewer for any airport in the USA.  The view not only give you update sectionals, but weather and a layout of each airport as well.