We are a free market and therefore everything is negotiable.
That said, I view asking price as an advertising tool. Depending on your market, it could be the hoped for desired price, or it could be the lowest acceptable price. It depends on the market and how well the seller understands the value of his/her house.
As a buyer, it is best to know the fair market value of the property. You base your information on the availability of other properties like it in the market and the value to you and the value to the seller. The free market will determine the rest.
1. If you want the apartment and no one else wants it and the seller must sell, then you could offer less than asking and the seller may accept it.
2. If you want the apartment and there is also other interest by others and the seller is confident that he/she will get his price, you may only get the property if you offer close or at the seller's asking price.
3. If you want the apartment and so do many many other people and the seller is receiving MULTIPLE offers, then if you want to be the one to get the apartment, you may have to offer OVER asking price to security the purchase.
If you aren't workng with an experienced buyer's agent, consider hiring one to help you best negotiate for the property you wish to acquire.