I had declared them trespassed verbally on the spot, loudly, proclaiming they were no longer allowed on the property, that I was the owner and this property was mine and I would not be pushed around or intimidated. 

Just decided to get back into retail real estate too so, back helping fellow investors and Home Owners acquire property along with my own projects this should be fun lol.

For example, maybe you will get to 10, 20, 30 houses and then find an owner who has a large portfolio and all of a sudden you are at a high door count and now need to hire, need to build your policy binder, and all the other stuff that comes with running a business.

You may also be able to start sending letters to duplex owners explaining who you are and that you want to own and live in a duplex, etc.  

MattIRA sells and owner finances the property for 200k and gets 30k down payment.

For RE owners, death allows you to pass assets to your heirs and step up in basis, effectively eliminating recapture.

Me the owner or my realtor? 

See who represents owners frequently in your jurisdiction and get set up with them.

On a per-owner basis the policies will change for occupants over the age of 18. 

They might refuse since you are not the owner.