You are considering a luxury apartment building project that requires an investment of $12,500,000. The building has 50 units. You expect the maintenance cost for the building to be $250,000 and it will increase by $50,000 per year in the subsequent years. The cost to hire a manager for the building is estimated to be $80,000 per year. The property tax per year for the building is 3% of the original investment. After 5 years of operation, the apartment building can be sold for $14,000,000. What is the monthly rent per unit that will provide a return on the investment of 15%? Assume that the occupancy rate is 90% on average.