From what you write, it appears that you received the check from your own insurer. If so, your insurer is only obligated to pay the then-current (or "blue book") value of the van, so you can't get more from them. You could seek additional costs you incurred from the at-fault driver (e.g. your repaining costs), but would have to sue that person (and win, of course) to get the money. For smaller amounts (under the limits of your small claims court), you are probably best served acting as your own attorney ("pro se") in small claims court.