The Devil Upstairs — Anthony O'Neill

In a quiet corner of Edinburgh, Cat Thomas is going through hell. She's tried everything. He respects nothing. If your neighbour was making your life hell ... Would you call upon the devil?
Cat Thomas, a brilliant fraud investigator, has just relocated from Florida to a dreamy flat in historic Edinburgh. Everything seems perfect. Everything seems serene. Except for the unbelievably noisy wannabe rockstar upstairs. Soon Cat's blissful new life is in ruins. Desperate, she's willing to try anything.
When all else fails, she makes an appeal ... to Satan. And suddenly everything is eerily quiet. But her nightmare has only just begun ...