In general, costs for an apartment are constructed by two factors, initial costs and running costs.
Initial costs include deposits, key money, insurance fees, agent charges, and so on. Sometimes, cleaning costs or overhaul fees are also included in initial cost as substitute for key money.
Running costs include rent moneys and administration fees. Sum of them should be paid monthly. In rare case, small amount of neighborhood association fees are added.
These costs are negotiable, but the possibility of negotiation depends on sort of costs. In general, initial costs are more negotiable than running costs. To negotiate at an advantage, it is important to know market practice and market price in each area!