The Virginia law on damage to personal property is stated succinctly in Model Jury Instruction No. 9.070, as follows:
Where personal property is partially damaged, the measure of damages is the difference in value immediately before and immediately after the accident plus the necessary and reasonable expenses shown by the evidence to have been incurred by the plaintiff as a result of the damage. If, however, the cost of repairing the damaged property is less than the difference in value immediately before and immediately after the damage, then the measure of damages is the reasonable cost of repair with a reasonable allowance for depreciation.