Mitchell Investments has offered you the following investment opportunity:

$$ $$6,000$ at the end of each year for the first $5$ years, plus

$$ $$3,000$ at the end of each year from years $6$ through $10,$ plus

$$ $$2,000$ at the end of each year from years $11$ through $20.$

How much would you be willing to pay for this investment if you required a $12$ percent rate of return?