$3$ A company supplies its marketing manager with a new car every three years. They can either buy the car out$-$right or lease it for the three year period. The new car will cost you $30000$ but it will lose $20$ per cent of its value immediately and $10$ per cent per annum thereafter. Leasing the car will cost the company $300$ per month. Based on costs alone, should the company buy or lease the car?