And all that my daughter had to do was provide the priest with a nice lunch. There are other sound reasons, besides financial, to having your haunted site cleansed by a priest, minister or rabbi. It can be very comforting. You could say your own blessing and it might work, but it simply may not carry the clout it would if an expert said it. It should be noted that sometimes ghosts choose not to leave, no matter who asks them or how politely they are asked.
Some ghosts are just stubborn that way.
It is possible.