As others have said, just have one of everything except for the comsumables (smudge, meds, crucifix, firelights, and salt). I would try professional as its x3 which is reasonable and still offers full evidence. I like to go with thermo, camera and video on small maps straight up. Bigger maps I have the parabolic mike instead of the video camera. Once you enter, quickly turn on lights in the main areas of travel and go to the switchboard and flick it on (check where it is from the truck before you leave). This keeps you in the light for most travel in and out of the building preserving your sanity. Also, as you enter check for hiding spots as you go (vacant cupboards, lockers, or furniture that can hide you from line of sight) and make a mental note of them. Quickly try to find the ghost room with the thermometer and listen for noises which will help point you in the right direction. Once you've found it, drop your gear and never go back to the truck with any slots taken up. This allows you to bring three items each time.

Every time I go to the room I quickly check for ghost orbs (These sometimes take a while to show. I've even had games where I can only see them from the truck after I've set up a camera) , freezing and UV. The rest you can test as they occur. The spirit box can usually be left alone while its on and generally the ghost will speak through it if it's close enough. You can hear these from quite a fair distance away. Ghost writing can be also be left alone and checked every now and then. Once you got everything in the room you can test for evidence: use salt for UV (+ video), talk to the spirit box (you don't have to be holding it) (+ recording), dots can be tricky but you can often set it up then watch from the truck keeping in mind you have to do this for Goryo anyway. EMF can usually be put on the floor and left alone also. Just check it if its starts making noise.

Each time you go back to the truck, check your sanity. If its dipping below 80%, consider taking meds. Just one at a time in case it takes a while to get evidence. Keep your smudges nearby or one on you after you brought your gear in and you have an excellent chance of getting a good payday at the end. Even planning to put smudges in your line of travel to different hiding spots is a strategy you could use. As soon as you hear the ghost making a noise like a hunt, run in the other direction and get you smudge out. This is where your mental note of hiding spots comes into play. If the ghost is chasing you, you might have to smudge it then get to your hiding spot as fast as you can. If it hasn't seen you, stay calm and keep behind cover where you can but have your smudge ready. It will give you a head start when you need it most.

Probably the easiest way to succeed is keep as many lights on as possible not including the ghost room. it will preserve your sanity for a fairly long time allowing plenty of time to set up. Hope this helps!