Multiple Companies?

I would def talk to multiple companies. That's how you will make the most money. I am currently working with Travel Nurse Across America, and Trinity. I have also worked with AMN, but since they are such a large company they don't have the most pay.

Yes, many experienced travelers have multiple agencies. There are lots of good reasons, access to more assignments, the ability to determine fair market compensation, to have a Plan B (and Plan C) when your best laid plans go awry, and better negotiating power. Since success as a traveler is determined in large part on your ability to communicate with your recruiter, the best way to pick agencies to work with is to call many agencies and pick (say) five recruiters you can really trust and talk to.

The easier way is to pick one agency, usually a larger one, and stick with them. If you get lucky and pick the right one, loyalty and trust can be rewarded with better assignments (including better paying ones) and with some agencies, loyalty bonuses. Because it is easier, that is what a lot of travelers do, until something damages that relationship (often through no fault of your own) and you are stranded with no Plan B. You can end up very lucky indeed and the one agency plan can succeed brilliantly with a lot of work saved on breaking in new recruiters and going through the paperwork mess.

How to plan your travel career and the size and number of agencies you pick can depend on how long you intend to travel. One assignment, does it really matter? Probably not. Two years? More? I started my career with one agency and stuck with them for four years. It ended badly, but perhaps for the best as I immediately started making more money playing the field. I have now been traveling for 18 years and learned by experience that agencies are a business, they are not your friends. Even if they were your friends, it is a mistake in my opinion to put all your eggs in one basket. But my opinion is not the only "right" one out there, there are different pathways to success.

As far as NYC goes, American Mobile and White Glove are probably the best option (note I didn't say best choice).