I'm inclined to MFH looking at it from the scalibility point, from the maintenance, mgmt point the ability to acquire more units on 1 transaction and 1 financing.

Your guests appear to have the ability to run a brothel with or without your cameras up and running.

For the under-prepared, here's a split-up of all the fees that I had to pay:a) Account Setup Fee: $95b) Bill Pay Fee: $15 (A bill paid to the city of cleveland for some permit)c) Lease renewal fee: $195 (That is right!

We live in Los Angeles county but buying anything here is crazy expensive and rent control limits any ability to profit anything. 

Demonstration of the ability to find a niche and exploit it.

A desire and ability to share their knowledge4.

If we buy a home subject to from a seller who is facing foreclosure, and that seller then has to rent someplace to live, how will the existing loan impact that ability?  

The question is, do you have enough equity in your current home / the financial ability to cover the cost of moving in 4 years if you use your cash on hand to buy another rental?  

A desire and ability to share their knowledge4.

If you have the ability to purchase a duplex for 600k, there are plenty of well established areas I would put my money into.