Did you return the apartment in the same condition you received it? Stains, dirty appliances, dirty bathrooms, repairing wall holes, and repainting walls that you painted are all chargeable. For some bizarre reason, many tenants think that cleaning, painting, and repairs for stuff they've done is included in rent. "Normal wear-and-tear" does NOT include dirty, stains, tenant painting, or repairing wall holes.
Wall painting and carpet replacement are debateable. Some properties estimate wall painting to last 12 to 18 months. Rental carpets generally can last 3 to 10 years -- depending on the quality. Unless the carpet was new when you moved-in, the carpet charge should be prorated based on the expected remaining lifetime of the carpet.
If you think you are being cheated, appeal the charges in writing via Certified Mail and request copies of the landlord's invoices, work hours, and repair items. Landlords often overestimate charges because most tenants do not contest charges, so they may be willing to offer an additional refund just to settle.
Also, if you paid a cleaning or administrative fee, then the landlord should itemize how that was spent.