Calculation to determine how much to save to reach goals?

[Brooklyn Owen]

I finished reading J Scott's and Dave Meyer's new book, Real Estate by the Numbers. J Scott is a great author and the book was super helpful. But, it is desperately missing an index and makes it incredibly difficult to lookup specific calculations I need to make. Does anyone know where in the book or simply what calculation I need to use to determine how much I should be investing each year to reach my financial goals?

[Amit Chawla]

I have used the following formula to see how much I need to invest.  This is a total amount so you would have to modify it to reach your specific goal.

First start out with how much money you want to make off of real estate yearly.  Lets say its 200k/year.  Divide that by your annual cash on cash return (in this example lets say 12%).  In this example that comes to roughly 1.67mil.  So you would have to invest 1.67mil in cash or equity in order to get 200k in yearly rental income. If you take that 1.67 and divide it by how much you have to put down (20%) this comes to about 8.3mil in property value total.