Others,  will argue that ARV must be considered to come up with your strike price.  

How do you strike a deal aggressively without having a bank back your deal?

Sending them letters or even striking up conversation if you can. 

Cash flow in your business will support growth and allow you to leverage your equity.You'll want to strike a balance between those two.

You could try and master lease the property from the owner and have an OPTION to buy at a preset price of 550k.This way you are not taking on personal liability but putting in a little bit of money and time and if you improve the value you have a strike price well below the new realized value. 

I just want to experience how people do it in real life before I strike out on my own. 

One that strikes me route now has tenants that are current, but somehow the Note is in receivership.

If you can help them understand the local market and you strike a deal that eases some of the pain points you might have some luck.  

FYI all your home info (prop taxes, mortgage, permits) are now easily accessible via City of Los Angeles on ZeneHome

That doesn't strike me as correct.