This is a video of using two saws to complete a trench cut against construction. It is quick but requires practice and coordination.

Two Saw Trench Cut

This is training video only.  Proper PPE including SCBA should be worn on the fire ground. 
We chose this spot at random in order to make the video.  This might not be an ideal spot on this particular apartment complex.

Take some time to review the difference between trench and strip ventilation.  Here is a good article from Fire Engineering.