I have invest some money on ghost hunting equipment, like K2 meter and the spirit box which can be purchase at ebay, it is one of the best that has been use in Ghost Adventures and other ghost hunting show.
I have done numerous "ghost hunts" and have had many good personal experiences, if you want to investigate a place
1. Don't go alone. ever at least until you know how you will react when seeing a ghost, being attacked by one, or hearing a disembodied voice whisper loudly in your ear.
2. Invest in a decent digital voice recorder to do EVP's (Electronic Voice Phenomena).
3. Take a good camera, you phone camera will NOT suffice.
That is all the equipment you will need to do a very basic investigation. Next, BE PATIENT, time means nothing to a spirit, they talk, appear, and make themselves known when THEY want to! BE RESPECTFUL you do not want to piss off an already angry spirit they can follow you home.. really, also be polite say please and thank you good manners pays off. When you ask questions give a fair amount of time for a response before asking another question you can talk over an EVP and not know it.
When going over your photos NOT EVERY BRIGHT SPOT IN A P