The price of a replacement key can vary by community, costing a renter on average between $100 and $400. Look over your lease agreement for the actual amount you might owe for a replacement apartment key. Metal keys may have a cost associated with them if the landlord has to call a locksmith.Click to see full answer. Also to know is, how much do fob keys cost?“The cost to replace the latest key fobs can run anywhere from $50 to as high as $400 depending on the brand,” says Consumer Reports automotive analyst Mel Yu. And that’s just for the fob. Add another $50 to $100 to get replacement fobs programmed to work with your car and to have a new mechanical backup key made. how do apartment fobs work? Each person issued a key fob has one programmed specifically for their use. For example, in a condo building where a fob is used to enter into the front door, each resident will be issued a similar item, containing the same information on the fob that allows them access. Also question is, can you copy an apartment key fob? In order to duplicate an existing key fob, you’ll need a “clean” fob to copy its information onto. 125khz key fobs are the kind most commonly used to gain access to office buildings and apartment complexes.What is FOB apartment?Key fobs are personal devices, which are small enough to be kept on a key ring or in a pocket. They are used with access control systems programmed to manage entry through one automatically locked door or throughout an entire facility.