Within three (3) months after his appointment, a personal representative, except for a special administrator or a successor to another representative who has previously discharged this duty, shall prepare an inventory of property owned by the decedent at the time of his death, listing it with reasonable detail, and indicating as to each listed item, its fair market value as of the date of the decedent’s death, and the type and amount of any encumbrance that may exist with reference to any item.