Any rental agreement shall state whether any portion of a deposit is nonrefundable and written notice of this fact shall also be provided to the renter at the time the deposit is taken by the owner or his designated agent.
Deposits are kept as a guarantee the tenant will pay the rent and not damage the apartment. 

State laws place no limit on the amount landlords can charge for security deposits. When you give the landlord a deposit, be sure to get AND keep the receipt EVEN if you give the landlord a check or money order. The amount you give should also be on the lease. Verify the correct is on the lease.

However, some cities may have enacted their own laws with respect to this.

The balance of any deposit and prepaid rent and a written itemization of any deductions from the deposit together with reasons, shall be delivered or mailed without interest to the renter within thirty (30) days after termination of the rental agreement or within fifteen (15) days after receipt of the renter's new mailing address, whichever is later. 
If there is damage to the residential rental unit, this period shall be extended by thirty (30) days. The renter shall within thirty (30) days of termination of the rental agreement, notify the owner or designated agent of the location where payment and notice may be made or mailed. GIVE YOUR OLD LANDLORD YOUR NEW MAILING ADDRESS OR YOU MAY LOSE SOME RIGHTS.

If the owner of a residential rental unit or his agent unreasonably fails to comply in returning the deposit, the renter may recover the full deposit and court costs. 

If the owner is the prevailing party and the court finds the renter acted unreasonably in bringing the action, the owner may be awarded court costs in addition to any other relief available.