Founder / Lead Researcher & Investigator for Normal Paranormal
As an investigator there is always the possibility of being followed home after a case. And yes, even as a researcher, you may inadvertently open yourself up to inviting something in. So the question remains...are you protecting yourself to minimize the risk? And what would you do if something actually DID invite itself in?
All prospective investigators must ask themselves this beforehand so they know what they are getting into. The field of paranormal research is fascinating, but not to be studied carelessly. And although it's unlikely, it's certainly a good idea to be aware of it in order to take the steps necessary to prevent it.
This goes for the unseen forces around you, as well as the environment. The entities you are trying to attract were once living human beings, just like you. And if you're demanding that they "show themselves" you're just going to upset them...or more than likely, receive no interaction at all. Would you want some stranger banging on your front door, demanding you come outside and talk to them? Probably not. In fact, you'd probably call the cops or your husband to go chase them out. Well, same goes for the other side. Who's to say, they're not calling on someone bigger and a lot more vengeful to follow you out after you leave?
Don't promise on things you can't deliver.
For example, if you're a parent to the living, don't ever promise to give that spectral child wandering about a place to stay. That's how entities can become attached to you. It's a kind gesture at first, but then once that entity starts waking you up in the wee hours of each and every morning, you'll wish you never "adopted" them to begin with.
Re-establish the ground rules of the investigation.
By reinforcing the fact that you have limited ability to interact on their level, this will display that you are at least trying to open up a line of dialogue which will prevent them from becoming frustrated and desperate. State that even though you may not have heard them while they were communicating, you still need to go over your recorders to see if there's anything that you missed. This also shows that you're not simply blowing them off if they have been generous enough to have attempted to communicate with you in the first place.
Be firm and to the point that you are leaving.
State that no one else is allowed to follow you out of the location. Make it clear that if there's anything left for them to say, it will just have to wait until next time when you or another researcher returns.
And always thank the entities for their time.
Again, respect will go a long way in the field...and beyond. Word gets around on the other side, or so I'm told. This might explain why some investigators have better luck than others.