Does he want them for commercial use? If no, then this would not be considered a commercial act. If it just simply, "Hey you have a drone, can you come take some aerial photos of my house for me to have?" Then I would see that as not requiring a 107 license.
Now if your friend was wanting you to do that, so he could use the pictures in a real estate ad, I believe that would be considered a commercial activity, even if you weren't being paid. I know plenty of people will say that it is not, because of no exchange of money, however the FAA has stated it is not about the exchange of money but about the intent of the mission/captured footage.