Look at attached flyer for "7579 Chrysler Dr, Detroit, Mi. Assume you have to invest 

$10,000 for each unit and that fixed and variable expenses are 40% and no vacancy. What must monthly income be to achieve 12% capitalization rate? 

Monthly income = $47,880/(1-40%) = $79,800

Step-by-step explanation

Value of the Detroit as per the flyer = $399,000

Capitalisation rate = 12%

Net operating income = Value / Capitalisation rate

NOI = $399,000/12% = $47,880

NOI arrived above, is post expenses for the detroit @ 40%

Monthly income from detroit = NOI/(1-Expenses)

Monthly income = $47,880/(1-40%) = $79,800