A financial consultant firm has presented you with an investment opportunity that will give you the following stream of cash flows: nothing for the next $4$ years; starting at the following year, an amount of $$5,000$ per year until year $14$; and after that year, then an amount of $$10,000$ per year until year $20.$ If your required rate of return $($APR$)$ is $12\%$ compounded annually, what is the future value at end of year $20$ of these cash flows?