We are talking about an 11 year old truck, which may have 150K on it, and don't know the history....you want to invest 10K(kind of the high end), offer 8-9....
But have the vehicle checked out by a good garage before buying it....road test, put on lift, check underneath, look for leaks, etc,. and any maintenance history would be helpful.....you don't want any surprises down the road...