Charges must still be provided in writing, in detail, and within 30 days. If you disagree with the charges, discuss them with the landlord. Refusing to pay charges in excess of your security deposit will usually result in legal action by the landlord.
Security deposits are a normal element of apartment rental.
The Pennsylvania Landlord-Tenant Act specifies how deposits are to be received, maintained, applied, and returned or kept by the landlord. Knowing your rights and meeting your obligations under the lease agreement are your best guarantees of recovering your deposit. For more information or for specific circumstances, consult the Housing Resource Center or seek legal advice.