I wouldn’t recommend Hoboken because there is only one train line - Path. I would recommend Brooklyn as well. My daughter works down on Wall St and she lives one stop away from Manhattan in Brooklyn. Almost every subway stops a block or two from her apartment, so it’s easy for to get to both east and west side of NYC. A lot of young people are living down in lower east side, but it would be harder for OP’s to get to work from the east side. I would look at West Village or Murray Hill area. From Murray Hill he could walk to work, and rent is cheaper there.
He should budget around 2000-2500/mon.
My kid’s first and only roommate was a friend from school. A lot of young people move to NYC after graduation, so I would check out students from his school first.
My brother lives on 55th and my cousin is moving from a studio on 45th and 8th to a 1br on 55th and 7th. I find that midtown neighborhood a little odd, it’s mostly office towers and tourist stuff, but it sure is convenient to everything. Both of them walk to work, which is a perk that is hard to put a price on.
Hell’s Kitchen…lol, they call it “Clinton” now 
I grew up in Morningside Heights/Harlem and love that neighborhood but I think you could get closer than that working on 42 and 6th. My friend’s place in Hoboken is sweet, and she has tons of cafes, bars, parks, etc she can walk to, the train is right there, and ferry options.
@oldfort Sure Wall street area to Brooklyn is fine, but Midtown West to Brooklyn is not so fine. Most people take the bus to Hoboken when they work in midtown and its easier than the subway to a lot of areas in Manhattan. Hoboken is an incredibly nice place to live.
Murray Hill is nice and good suggestion. Kips Bay/ Murray Hill are basically the same area.
I personally would like to walk to work, so 30s - 40s east is probably best.
If he is going to be working at a bank, or at any place with very late hours I would want to stay in the city, not Hoboken. He will want to be able to Uber home late at night, possibly later than the path trains will still be convenient.
There is a building around 12th and 42 that is a little removed from the popular areas so it is a bit less expensive for the type of building that it is (river place and Silver towers) . There is another building that I know of around 8th and 50st that is also nice called Longacre House . As far as finding a room mate, check Craigs list for possible sublets.
If he can find someone else from his school moving there as well that might be a good place to start.
I work on 31st St right near Penn Station and we have several young people commuting from Hoboken on the Path. Hoboken is not as inexpensive as it used to be but very convenient and very lively place at night with lots of bars and restaurants. I would also recommend Astoria as a more inexpensive area, more so than Williamsburg for example. My d lives in Williamsburg/Greenpoint border and it is a really quick commute to midtown except for weekends with lots of transit shutdowns for repairs. I can get to my office from her apartment in 20 minutes. The 30’s on the east side are a good area for working in midtown as is the Village but the Village is no longer inexpensive. I have colleagues who live in the Village and can walk back and forth to midtown or quick/easy commute by bus or subway. You can also look on the Upper West Side as an easy commute.
You want to be near subways.
@TurnerT - you do see that ACF23RBD all stop around Borough Hall in Brooklyn, and all of those subways go to midtown west where OP’s son will be working.
Bus is probably the worst kind of transportation in Manhattan, especially during rush hours. Subway is the way to go. That’s why apartments near subways are more expensive. There are many new apartments west of 9th Ave, but there is no subway around there.
My daughter lived in the Wall Street area for a while last year; it was a room in a three bedroom apt in a high rise building where the tenant was away on a job assignment for 6 months. Her room was $1500 and she found it on Craigslist. She lived right near the Fulton Street subway station and South Street Seaport. The area is way more residential than it used to be with grocery stores, coffee shops and nightlife keeping people out on the streets and using the trains late at night. It’s really not a bad place to live, though I don’t think she picked up much of a community feel there.
So to answer your original question, the best way to find a shared apartment situation on Wall Street is on Craigslist.
She in Bushwick, so I think yes north Brooklyn just past Williamsburg, rents are cheaper. Here is a great subway stop guide to Bushwick, wonder if other areas have this
http://bushwickdaily.com/2013/02/a-newbies-guide-to-bushwick-subway-stops/
I’m thoroughly confused what part of town OPs son is going to be working, not that I could help, but I guess it doesn’t matter as long as he knows what transportation is near.
my son will be working near 42nd and the avenue of the americas 6th
i know my ignorance screwed up the title of the thread
thanks
@fleishmo6 you should also ask around your neighborhood to see if any of the students a year or so ahead are already in the City. They might know people looking to fill slots in their apartments 
How much night life does your S want? For that work address, I’d recommend Roosevelt Island. Straight shot on the F train. Not cheap, but cheaper than midtown. http://streeteasy.com/area/roosevelt-island However, there’s very limited night life there, so some young people dislike it.
My d also lives on 55th between 2nd and 3rd Avenue. Her commute is about 30 mins.She is rooming with the girl she shared her dorm with when they interned the previous summer. They worked with a broker to find the apartment. Lots of her peers live in Brooklyn.
Thanks to everyone who gave advice about places to live for my son. We moved him into an apartment in Gramercy. Great neighborhood, easy commute and seems to be safe with lots of amenities within walking distance.
Thanks again
Nice. Great neighborhood. Close to everything. He could walk to most places, and have access to most subway at 14th st.
Oh, want to share how he found the place?
He, I believe got pretty lucky in finding his roommates and apartment. Found two roommates who also just graduated and who were moving to NY to work in finance through social media, Symbi.The three texted, skyped etc and all three started online searches for an apartment.
The one came into an open house and it matched their list of what they wanted so they filled out an application. Most amazing part was they had no realtor fee and got qualified on their own without any cosigners/ guarantors. Had to provide copies of offer sheets from their companies along with the applications.
gotta give these young men credit as they totally did it all on their own. One was in LA one was in Maryland and mine was in Vermont.
Now fingers crossed for the next rung in the ladder of life.
Congratulations.