But there are a few other things any team needs to have or do prior to an investigation.
Permission
Always call prior to an investigation. With permission a team can feel safe and secure in investigating. Going onto another's property at all, or after hours (such as businesses and churches) is trespassing and people can be persecuted to the full extent of the law. A trespassing charge will result in jail time, a fine and will ruin the accreditation of a team.
Identification: Simple ID cards can be printed off the computer with a picture of each team member. Not only does this identify yourself to local law enforcement or to the owners of the property but it also lends validity to the organization.
A team: No, not the "A-Team" from 80's television, but a team of investigators. No one should investigate alone and if it all possible, no one should go off by themselves when investigating. This is not like Scooby-Doo where Velma always went off alone and Shaggy's companion was a dog. Stick together. Remember what you were told as a child "there's safety in numbers." If more than one set of eyes saw the same thing, it also validates claims of activities.
Spare batteries: Flashlights and equipment are a "given" in paranormal investigation, however, spare batteries are often forgotten about. It is a common belief that paranormal activity can deplete the energy in batteries, or if you haven't changed them from the last investigation they could die of natural causes. Some people bring a candle or lighter to check for drafts or to aid in seeing if a flashlight's batteries go dead. However, be very careful...you don't want to add arson to your trespassing charge.
Establish a Home Base: a vehicle or a room of the building can be "home base" for equipment. On TV shows they have the finances to support cameras being set up throughout the building or grounds and a team can sit back in home base and watch the monitors. However, most teams cannot do this, but a home base is still essential in case team members do get separated there needs to be a home base to meet at rather than walk around aimlessly. Extraneous equipment can also be stored and retrieved as needed.
A "Paranormal Log Book": or, a pen and tablet in Laymen's terms. Record times and events such as: "1:00 a.m. smelled the scent of roses in the "blue room.'" These entries can be coordinated with others entries and other evidence to further validate claims. Not everyone is going to have a camera crew following them that can be referred back to for places and times. Entries for where you are monitoring for movement can also be made such as: masking tape around porcelain doll, bedroom #1 for easy retrieval of the tape and to remember where you are monitoring movement. Colored pencils are also useful for drawing diagrams of rooms or buildings and noting where paranormal activity occurred.
Zip-loc bags: These come in handy for collecting evidence that might show a paranormal haunting.
Chalk or Masking Tape: A piece of chalk can be used to draw circles or make marks around or near objects to any objects being monitored for movement. Chalk will wipe off easily or outside it will wash away with the rain. However, for buildings or homes that are being publicly used or lived in, try a piece of masking tape (don't forget to remove it later); homeowners might not appreciate their place being all marked with chalk.
No Alcohol: This is not a "dare" at some teenage party, but a serious investigation. Stay away from imbibing in any alcoholic or illegal drug usage. Not only does this make your claims more real and less hallucination, but being intoxicated will ruin the accreditation of the group as well as future groups. However, it is advisable to eat a large meal prior to investigating so that a stomach gurgle won't be mistaken for an EVP.
No Smoking: smoking causes phantom smells as well as eerie mist on cameras.
Hair pulled back: a wisp of long hair flying in front of the camera will result in some vortexes on film. Keep all long hair under a cap or pulled back.
No perfumes: perfumes or heady bath soaps and washes lead to phantom smells in investigations
A Compass: A very primitive method to detect EMF fluctuations, and to keep yourself from getting lost, a compass is an essential basic tool.
Camera and Film: Most paranormal investigators recommend a cheap 35 mm camera using 400 speed film, because it gives the most "raw" exposure. Apparently cameras that utilize newer technology don't work as well. A disposable camera is one of the cheapest and best alternatives. Polaroid instant cameras are said to take interesting images as well, and give immediate results.
Tape Recorder: No self-respecting paranormal investigator would be caught without a tape recorder. A brand new tape should be used with each excursion. Not only do you not want to record over potential evidence, but tapes get contaminated when recorded over and over on and weird sounds from tape contamination can be mistaken for an EVP.
Dowsing Rods: Dowsing rods are "L" shaped metal rods that are held in the hands and have been used to find everything from water, to lost items, to graves, to paranormal activity. However, these are not a piece of equipment a skeptic or non-believer can use and see results. For those wanting to try dowsing rods, practice with them and attuning oneself to the rods is essential before an investigation can take place. Pendulums can also be used to detect paranormal activity.
A Small tool kit: Some electronic devices need screwdrivers to change batteries, you don't want to remember the batteries but not be able to change them.
A quick visit to dollar and discount stores, a search around your home and garage or even a visit to department stores can get all the basic equipment that you need. Carry and store in a backpack or fanny pack so it is always convenient and always packed. After a few times of investigating you will see which items you actually found useful or which items you don't need, and maybe even come up with some ideas for items you should have had.