If you don't know call a funeral home or visit with a friend who has been through it recently. Your attorney should be willing to give you an estimate. You don't want to be a deadbeat even in death. Plan to payoff your debts. If you are married your spouse probably has cosigned for everything you have borrowed.
Some people buy life insurance in order leave money to a special cause.
It is sort of like making time payments on the gift and being certain it will be given even if you don't live long enough to complete the payments. This can be particularly difficult if the assets are not liquid. A farm or a business that is going to stay in the family, for example. Your survivors will have to raise cash to pay the taxes if they want to keep the assets. Survivor's Annual Living Expenses Use your current budget as a starting point.