Realtor Issues - How to not pay them.

[Sarah Jones]

I have a property that I want to buy directly from the owner subject to. The owner agrees to sell it to me for 400k subject to. I'm concern about the realtor. They have a realtor. If i buy it directly from the owner, I know because they have a realtor I may be responsible to pay the realtor his commission. The owner is already 3 months behind on his payments. How do I buy it , make all the backup payments and avoid paying the realtor his commission?

I did not find the house on the MLS.. the owner is a friend ..