I am pursuing a diminished value claim on a vehicle that was rear ended and repaired. But I want to figure out the best way to calculate diminished value.

The van is worth around $11,500 pre-loss. I used NADA, KBB, and some dealer adds for similar models for sales to come to that approximate number. When I was still doing auto loans we would only lend 50% of the total NADA value so I am thinking 50% is the right target. But we weren't planning to sell it this year, probably end of next year so the diminished value might need to be off the projected 2016 value instead. I'm just not sure how to arm myself for once the insurance company calls me back.