Tech Innovators is considering the purchase of a 3D printing machine. The current machine, which is still functional, can be sold for $5,000. The new machine costs $150,000 and requires an additional investment in working capital of $25,000. The machine will generate $35,000 in additional annual cash inflows for the next seven years, after which it will have no salvage value. The required rate of return is 8%. Additionally, there is a setup cost of $3,000 in the first year. Calculate the NPV of the investment and decide if the purchase is justified.

Requirements:

1. Calculate the NPV of the investment.
2. Determine if the purchase is justified.
3. Include the salvage value of the current machine.
4. Consider additional working capital and setup costs.
5. Use a discount rate of 8%.