The law in plain English
Return deadline
Under Md. Code Real Prop., Sections 8-203, 8-203.1, 8-208, the deposit response usually has to be sent within 45 days of the move-out timeline described by the state rule.
Required notice
Maryland generally caps the deposit at 1 month's rent, with a narrow higher-deposit exception for certain utility-assistance tenancies, and the landlord usually has 45 days to send the refund and written list of damages.
This dispute type
Once the Maryland deadline passes, the dispute stops being only about the deductions and becomes a deadline-compliance problem too. A landlord may still argue damage existed, but Md. Code Real Prop., §§ 8-203, 8-203.1, 8-208 sets the clock for returning the balance and explaining any amount withheld.
Penalty leverage
If the withholding was wrongful or in bad faith, the exposure allowed under the statute is: Landlord forfeits the right to withhold; you can recover up to three times the amount wrongfully withheld, plus attorney's fees