Well, at least with the ksports you could raise it up some. Auto, NA, slammed with spacers and its FWD with over 100K. I think the coilovers and rims used are worth about as much as the car. Offer him 3 grand. Put it back to stock and sell it for 5K.
Also note that this is a 2.4i and a 7 year old car with over 100k miles. Yes, they just had the timing belt done, but it's not worth as much as their asking.
As I always say... Add up the parts value (not labor) that you have invested in mods, divide it by two, then subtract that from the KBB value of your car and that's how much you can ask for a modified car.
If it was stock, he might get away with asking for $10k...