Assume you are paying $$1,000$ per month on a $30$ year mortgage of $$150,000$ and are on payment number $12$ of the $360$ monthly payments. You notice that your home equity has only increased $($the principle owed decreased$)$ by $$650$ so far because early payments are mostly interest. You change jobs and get a $$500$ monthly raise. Assume you pay $$500$ extra each month on the mortgage starting with payment $13,$ and doing so shortens your payment timetable to just $21$ years total. How much extra have you paid into the equity of the home?