If you want to lease the best NYC apartments to live, then you will have to take care of some of the real state agencies and agents. The agents will provide you a listings of all the available NYC Apartments so you can go through that listing and find which is the nice place and moderate prices are available and you can go their personally and decide if you like it or not.
If you are using the help of an agent than you need to pay him some commission for doing the job for you. They usually charge one month rent or 15% of one year rent. Sometime even though you get help from agent in finding a living place for you they don't charge you with any fee because they get payment form the owner of the building as the agent works for him so he get money from the owner for bringing a tenant to their building.
You can also find a renting place which are owned by individual landlords like Condos and Co-Ops they are better choice to live but they are expensive as they are single units and owner puts many conditions to rent the apartment. The application fee itself cost you around $500 and it goes to managing agent. In C0-Ops you need to face an interview before renting an apartment the application fee is for Co-Ops only condos owners do not take any fee.
Buying an apartment in New York City is difficult job as getting the mortgage is very hard. The best option is renting NYC Apartments and it is the most convenient thing because you have various apartments to choose and can find the best apartment in the best location and utilize all the facilities available in the apartment building.