Property Damage Liability
In those "split limit" numbers there is usually a third number, indicating how much of the coverage is for repair or replacing the other person's car or other property damaged in an accident in which you are found at fault. Some states allow as low as $5,000 but understand that you will have to provide the rest, and if the other car is a Mercedes or the like, there will be a "rest". Most recommend $50,000 worth of coverage for each vehicle and a total of $100,000.
You will want to put your cookies into bodily injury and property damage insurance, particularly when you have significant assets to protect. The increase in protection does not necessarily mean a huge premium jump, so when getting quotes, go up a few levels and see how big a difference it will make to your overall cost.