A manufacturing company's budgeted fixed manufacturing overhead costs are $160,000, and variable manufacturing overhead costs are $7 per unit. If the company produces 20,000 units, conduct a comprehensive analysis of the total manufacturing overhead cost and the cost per unit. Explore the implications of using different overhead allocation bases, such as direct labor hours, machine hours, and activity-based costing, on product costing accuracy and profitability analysis. Discuss the advantages and limitations of each allocation method in various production environments.