J&G have us believing that you walk into a client's home. You do a breezy interview, note the hot spots and stories, set up the equipment and then promptly pair off; Amy and Adam, Tango and Steve, Jason and Grant. You walk around. You ask some questions. You sit back and get that KII meter going. Same ol'/same ol'.
Every case is different. I would never be a professional exterminator and go into a home and set up rat traps. I'd find out if the problem was termites, cockroaches, silverfish or other. When I discover a baby's room, I might not spray toxic chemicals. I'd look for pathways and patterns for the critters so I can keep more raccoons from getting in the attic.
Adaptability depending on the terrain, reactions and the circumstances!
When you've done the proper pre-screening (this can involve extensive questionnaires and a few weeks to a month's worth of logging activity by the clients), you then get a picture of just how you might want to approach the situation.
It gets even more hairy when you arrive at the home to find out that the kid's room where the activity is happens to also be the home office where two computers, a router and modem and more equipment stay on day and night. Depending on what you find, you have to be ready to change your game plan.
Does this haunting seem to be aggravated by a particular member of the family? You might decide to sit with that person and do a little EVP session at a table with no one else present. You might also consider taking them out of the home so you can test just how much is dependent on their presence.
House has a really high baseline EMF? Try doing a little EVP session with the power on and then with the breakers thrown.
One room not getting any action? Focus on that room.
Why not track it with something often times better than vision--hearing! A simple fishing wire string with a jingle ball hanging by a tack from the ceiling--these can be placed going down a hallway where footsteps are heard. If the windows are closed, people sitting still and air turned off, you can track something that actually makes the balls jingle. What can we figure out from this? You'll understand if you're dealing with a residual sound or an actual entity propelling itself through the course.
Try novelty. In some cases, all the begging, pleading and goading might not work. But, what if you sat down and rocked on the floor and talked to a dolly with the recorders going? What if you and another team member spoke a made up language? Hmm....
The bottom line is there is no cookie cutter way to go about this and if an outside-the-box investigator goes about this, each hunt can provide something new in understanding phenomena, knowing what incites it, coming up with new testing methods and--(say it with me--you hear it enough here) "furthering the field!"