Rent nothing until you have seen it and the areas around.
Also, will this be fully furnished
Can't agree more. Never sign the contract without first making sure that the apartment and the neighborhood meet your requirements, and without going over the contract carefully with a native Pole.
Don't try to do this over the internet; it's not going to work. As I said before, it would be best if your future colleagues found a suitable place for you. In any case, when looking for an apartment, always have a native Pole with you to translate and explain.
Furnishings vary from apartment to apartment. You have to see what is in the apartment to decide; some apartments are provided with good furniture, others with cheap old junk that's dirty or falling apart. Chances are that you will have to by a desk and desk chair.
1500 to 1900 PLN per month is about right for a one-bedroom apartment in £ódź, all bills included, except internet/TV/phone. Generally, the cheaper the apartment, the less desirable it is, either because it is run down, or because it is in a bad location. Be careful to check out the windows and the heating. An old apartment with bad windows can cost a fortune to heat in the winter. Nice, new apartments in desirable neighborhoods are going to cost even more than 1900 PLN. Depends on what level of comfort you want.
The prime consideration for picking a neighborhood is proximity to your place of work. A cheap apartment may be no bargain if you have to spend two or three hours a day commuting to work. You'll also be probably happier as a foreigner living nearer the town center, rather than in some god-forsaken housing estate on the periphery, so aim for a location between your place of work and the town center, but with easy access to both, especially your place of work.
Be very careful of apartments that are well below the market price. If they are, there is usually a good reason for it, and you should make sure to ask exactly why. It can be something like intolerably noisy neighbors, or bad plumbing.
Also, make sure your apartment has a good clothes washer. Laundromats are few and far between in Poland, and they are very expensive.