1. Make sure that your video equipment is working well and that you have it set up for good angles long before you have to start the shop. Make sure that you know how you are going to hide it and that you won't do anything silly like pull the plug out as you stash the recorder in your pocket/wherever... Don't forget to put the memory chip into the recorder....
2. Make sure you know your scenario and which questions you must ask vs. which ones you are supposed to wait for the leasing agent to ask.
3. Practice before going. Know where your camera is pointing at all times and find ways to point the camera at the target while looking at something in a different directions. Of course, you need to look natural doing it....
4. EPMS has lots of details in its narratives that the camera may/may not pick up. Be ready to observe those details.....
5. Use your iPhone as a back-up audio recording device, just in case......
Hard work builds character and homework is good for your soul.