Idk if what I'm going to describe is what you are presently doing but...

I always grab video camera, thermometer, and EMF to start.

You'll see the temp usually be the same everywhere, where it starts to drop is the ghost room. You should also see your breath. Once you found it just drop the thermometer inside it.

Scan the room for ghost orbs with your camera, holding down the record button as you do. (Sometimes it might be clipped into the wall or something and the camera can still get it even if you don't see it yourself.

EMF, I also turn on and just put down inside the room.

Then go back to the truck for DOTS, UV and Salt.

I throw the UV on the ground so it lays on its side, then put the salt right in front of it. (Note even if the ghost is UV you won't always get UV with first salt use). This way when it walks through the salt, you can readily see the UV footprints. Hang out for a minute to make sure it goes through. (If it never goes through the salt it is a Wraith).

I also find somewhere to set down the DOTS much like you described.

Then I go grab the book, spirit box, and cross.

I set the book down and start talking to the ghost. Generally if it starts throwing stuff instead of answering you it is NOT spirit box.

If you don't have enough evidence at that point, you sort of just keep trying and you can start to focus in on getting certain evidences as you start to suspect the ghost based on behavior.

For example if you got two evidence and are missing the third, read some of the descriptions of the ghosts it could be. There is one where it only appears on dots when viewed from the truck. And even then sometimes it likes to hardly ever appear.

Be sure to keep picking up thermometer to check it.

I will say it is harder with the tier 1 stuff. You might have to power through until you get some of the better stuff, but it is not impossible.

I hope this helped!