I'm looking at a duplex and the owner offered owner financing on it, asking 10% ($34.9k) of the asking price ($349k).

I want to reach out and get feedback on where I would be able to find off market self storage facilities and how to approach the owner?

Yes I have known it to work because the owner is not a push over, enforces policy and can make it run good......however, do you have the right personality to do this, AND if you move out can you continue to have the house run smoothly with no one in charge.  

Ask to speak with some of their current owners and current/former tenants.

I looped in the owner of the company but things are still pretty rough. 

The problem is that you don't get an opportunity to do an inspection before you buy.If you buy pre-sale from the owner, you have arrears to bring current, getting the owner to move after you have solved their problem and taken the pressure off, along with the previously listed concerns.

What I can also tell you is that as an owner in NY, the landlord laws are very much designed to protect a tenant as opposed to here in Detroit where the laws are designed more fairly to protect both the tenant and the landlord.

I'm an independent agency owner that represents both Foremost and Obie.  

I'll be in the market for a duplex/triplex in the $400k range that I will owner occupy and use a 5% down loan.

So he bought up several owner financed properties that offered 0% down, and he cash flowed.