ghost, or spirits, or spiritual beings, do exist. they encounter us, not the other way around. they have different levels of existence. their status as good or bad is about the same as a living person's. it is not wise to deal with spirits. they operate on a different playing field and unless you can keep up and are prepared for ALL that you will encounter, it is best to leave them alone. malevolent/demonic spirits are tricky. they disguise themselves well and are very manipulative. so if you insist on seeking out the spirit world and encoutering spirits, best you prepare for the good, the bad, and the down right evil. i suggest you learn how to protect yourself before you begin.
why do spirits haunt places? simple, they have an attachment. perhaps the spirit once lived there, or knew someone who lived there, or simply had a fond memory of the place for any reason. when alive, the spirit may have simply thought the place was beautiful and in death chose to reside there for eternity. this is what is referrred to as an "earthbound spirit". earthbound spirits choose to stay here on earth for one personal reason or another. some, in fact, may not even be aware that they are dead. another reason why you must excercise extreme caution when dealing with spirits. do you really want to be the one who breaks the bad news? i think not.
as a medium, the choice of encountering spirits is not our own. we encounter them on a daily basis. the only choice we have is how to deal with the encounter. at times it is best to follow the rule of thumb to only speak when spoken to. most spirits want to be left alone. those who wish otherwise will make their presence known. again, when dealing with a spirit that wants to communicate with you, exercise extremem caution. unless you are trained in what to do and how to protect yourself, i stronly suggest you command the spirit to leave you and seal it with a faithful prayer. afterward, do not speak of the spirit for it will cause it to return to you.
so yes, "ghosts" are real. they are deeper than the mist that may appear before you. there are many layers to them. an uneducated, untrained person need not go in search of them because once you find what you are looking for, you may regret it.