A five$-$year project has a net cash inflow of $$20$K$,$ $$25$K$,$ $$30$K$,$ $$20$K$,$ and $$15$K in the next five years. The minimum required rate of return is $20\%,$ Based on the net present value $($NPV$)$ concept, what is the maximum level of initial cash outflow $($investment$)$ to keep the project justifiable?