90K is a BIG salary. Most people do not make that much. I made 60k while I lived there and that is considered pretty good. I was in Baltimore. I was comfortable with my car and had enough to shop, go out and even save quite a bit each month. I lived with a good friend. We shared a 2 bedroom/2 bathroom apartment so we were able to split electric and cable and internet bills. So that helped a bit. But I had plenty of co-workers that lived alone on that salary and were very comfortable. They went to happy hour almost every Friday and partied all the time. I don't live that lifestyle, so I went out with other friends. But the point is, 60K is pretty good in a lot of cities.
I have a bachelors and work in healthcare. Now if you do not have a university degree that is in demand and will get you a decent paying job fast, things will be harder. I personally knew families that struggled on 30-40k a year. You must also think of taxes. When you are given an offer, they give you pre-tax amount. After federal, state and city taxes, social security, medical/dental insurance, medicare/aid all come out of your paycheck, about 1/3 will be gone. so let's say you a get $1000 payslip, you only actually get $700 in your bank account.
Electricity, let's say about $100-200, depending how much heat or air conditioning you use. Internet $60. You could get a package deal with cable and phone if you want for varied prices. Car insurance, if you just get there with no US driving record could cost you about $100 a month or more. A nice one bedroom apt for $900, maybe less if you know how to shop for specials. We had a decent 2 bed/2ba in a gated community for 1200/mo, with a pool, hot tub, club house, water included. Gas about $200/mo with a 30min commute to work and weekend outings. Groceries $300-400/mo for 2 of us (2 girls who eat healthy, not too much processed foods). Cell phone was $100 but that's because I had the full internet/GPS/phone deal. You can also find prepaid cell phones and pay as little as $30-40/mo if you're not a big talker.
You have to shop around to get the most for your money and it will take a while if you are new tot he country and the way things work there. If you can afford a car, try to live away from the bus routes. Usually safer areas. Around September/october you will find specials for apartments.
NOTE: These were prices for BALTIMORE city area. Virginia, Florida, Texas, Georgia are cheaper states to live in. New York city, Chicago, Los Angeles, Washingon DC are some of the most expensive paces to live. Many immigrants live there, and many new comers go there to find the American dream and stay with people they know. But it is not worth it if 10 people have to live in a small space. Too many people pay a lot and struggle only to be less comfortable than they were in their own countries. It's not as easy as you see on TV. Stay with people you know to begin, but as soon as you can you may want to find cheaper cities to move.
I have a bit of concern about my number which is above 19k. I really hope we gonna fit in the limit!