There is a need to calculate life of machine to solve this problem.

8. [Option to wait] Your company is deciding whether to invest in a new machine. The new machine will increase cash flow by $180 per year and forever. The machine is currently priced at $2,000. The cost of the machine will decline by $25 per year until it reaches $1,800, where it will remain. If your required return is 8%, should you purchase the machine? if so, when should you purchase it? What is the value of option to wait