Final answer:
The method providing a more detailed and accurate product cost by allocating overhead based on activities used in the product's creation is activity-based costing. It differs from traditional costing methods by providing a clearer picture of true manufacturing costs. Activity-based costing is especially useful for diverse products consuming resources differently.
Step-by-step explanation:
The product costing method that is more detailed and complicated than conventional costing methods, but provides more accurate cost numbers, is known as activity-based costing. This method allocates overhead costs based on each product's use of activities in making the product. This approach is in contrast to traditional costing methods, which may allocate overhead costs based on simplistic and sometimes arbitrary measures, such as direct labor hours or machine hours.
With activity-based costing, companies gain a better understanding of the true costs of manufacturing and selling products. This is particularly useful when dealing with diverse products that consume resources at different rates. For these reasons, activity-based costing can provide more precise product costing and can support more informed decision-making.