Over $3k down the drain over 5 years?! OMG, the Humanity. Or, his rent represents $96000 that didn't earn him one cent of equity over those 5 years. Meanwhile, the price of property (generally) increases, interest rates are unlikely in a couple years to be as low as they are now, and if he's eventually going to buy, he's 60 months further behind when he would have complete ownership (and not have a mortgage payment at all - just interest.) I agree with ElFenix - he needs to be sure this is where he's settling down.
Even though you don't directly say it, or may not have event meant it, I read this statement like all that money would go to equity.
I don't know how much houses cost in NYC. If Trulia is to be believed, the median price is over a million dollars:
http://www.trulia.com/real_estate/New_York-New_York/ of course, this is within the city and not a suburb.
Let's look at Jersey City, that's $300,000
http://www.trulia.com/real_estate/Jersey_City-New_Jersey/market-trends/
Let's figure 20% down (which the OP currently doesn't have), and an Interest rate of 4% (low compared to the average). 42% of all his payments over the course of the loan cover just the interest. In addition, there is property tax.
According to this article
http://www.northjersey.com/news/Report_Average_NJ_property_tax_bills_grow_to_record_high.html
The average property tax in that area is around $8000 a year. So, let's figure this out.
He would pay 1,145.80 a month for the loan (no property tax included), 480 of which pays interest (averaged out over the course of the loan, initial payments would actually be more towards interest, but later payments would be less).
He'd then pay 667 a month (assuming average rate) in property tax. Add these together, that's $1147 a month just in interest and taxes.
There are other things to factor in, such as increased homeowners insurance rates. Increased utility bills (due to larger living space), repairs, and other things that would need to be bought due to home ownership. Also, the extra time to keep the home up is also worth money.
This amount would be greater if he went ahead and bought without 20% down. Not only would the monthly payments be higher, he'd have to also pay PMI. You also have to factor in what that 20% could bring in if it was invested rather than used for a down payment.
I stand by what I said earlier. Stay where your at now, and only get a house when you have a family.