Living in what some would consider a “crappy” apartment is pretty awesome, and I am not being sarcastic. And if I found a deal, so can you — with some catches, naturally:

The view from my hood.
• You have to learn to share. I’m not usually one to use if/then statements in this context, but if you make very little money, you’ll have to tolerate shared living. When you’re searching Craigslist, choose “rooms/shares.” I’ve found both places I’ve lived in Manhattan via Craigslist shares, and they turned into wonderful friends. And I’ve never paid more than $815/mo. in rent.
You are the best judge of character regarding who you can and can’t live with, so I’ll leave the “make sure they’re nice” stuff for someone else’s blog. Beyond a safe/clean/healthy environment, if you have expensive taste or a bevy of neuroses/deal breakers, New York City living will be an adjustment.
• Spend as little as you can on rent. I would say no more than $900. Instead, spend your money on experiences. (Plus, you won’t be home much anyway.) When you look back on your first 18 or so months here, you’ll get more happiness from the things you did than the countertops in your kitchen or the size of your bathroom. And, if you’ve been in Manhattan a year or so and the mood strikes you, by all means, move if you want to move. New York City is huge and there are tons of great neighborhoods!
• Before you sign anything, ask about this stuff. The amount of light the place gets. The noise level from the street — on weeknights, early mornings and weekends. (Even if you don’t face the street, you’ll still hear noise.) The New York City Homicides Map. How close you are to fire stations, hospitals, police stations. Any construction projects on your street, and how long they may last. Pest problems, past and present. What the super is like. Heat/air and the flow or lack thereof.
If you’re looking for a place and wondering about something specific, leave it in the comments and I’ll give you my best answer!

What are neighborhoods that are cheap but also safe to live in?