I sympathise with your plight, and gotta agree with others in this thread - if there is something there, we Orthodox also believe it will not be a human “ghost”, but will be demonic and thus inhuman entity.
My Church teaches that these things vary greatly in rank and in potential for harm. But they are there to deceive and harm nevertheless.
In our Church, before we go down the priestly blessing or exorcism route, we try other remedies first - and see how they go.
We often install holy icons (blessed) in the house - those featuring Saint Michael The Archangel, Christ Descent into Hell and anything to do with Christs Resurrection are particularly powerful for demonic infestation. These are placed in the corners of rooms in most cases.
Prayers to Archangel Michael for intercession are often used by the family.
We often burn a perpetual holy light before the icons (obtained from Church at easter time), and often Church incense is used throughout the house. Sometimes communion bread obtained from the Schu Table in church is brought into the house - and kept rather than eaten immediately. This is very powerful against demonic power.
If a priestly blessing is required - we use holy water, and holy oil on all walls, doors and windows.
Good luck with this problem. You will know if the minimalist approach isn’t going to be effective, because the disturbances usually intensify in response to insufficient measures.
Sometimes, a Priestly intervention, and various church based rituals are the only thing that will do the job.