My question involves an injury that occurred in the state of: Colorado

My father caused an injury accident while backing out of his driveway. He was, unfortunately, sold a policy that did not insure him properly. He is now being sued by the other party for $800,000.00 above what the insurance companies agreed to settle for. He does not have anywhere near that much money or assets, although he does have some money and assets. The insurance attorney said there is no hope if it goes to court and he does not think that the other party will settle because "he sees your father driving a nice car and wants a piece of what your dad has." My father is willing to offer a reasonable settlement. My questions are: What is a reasonable settlement? and What are my father's options, if any, to protect his assets?