Marked Mod 24? Pre-model guns will bring a bit more. Box? The original box adds value. Original grips? Best is if they have gun's serial written inside meaning they are the ones that came on it, 2nd best is correct "diamond" style.
A 97% Model 24 in the most common 6.5" barrel with box and correct grips would have a $1,500 price tag if I were selling it and I would not negotiate.