The Boggart Fights Back by Susan Cooper

Set in Scotland, this is the story of a developer who only sees what money he can make from a development.  He's bought the farm that was there, is working on buying the castle, and he makes their grandfather a generous offer for his little grocery store on the water front.  But grandpa isn't selling.  So the man intends to drive him out.  The problem is that he doesn't understand that some of the legends in Scotland are real...

Margaret K. McElderry Books and Edelweiss allowed me to read this book for review (thank you).  It will be published January 27th.

Allie and Jay are visiting and they are willing to help their grandfather fight back.  They take around petitions, remove the ribbons from trees that are to be cut, and eventually ask the boggarts for help.  The noise from the developers construction and destruction has awakened the sleeping boggarts.  They are shapeshifters.  One of them had been the Loch Ness monster for a while but now they are almost invisible and only have shapes when they take them.

The boggarts begin by scaring him with Nessie but all that does is inspire him to build quicker and more.  They come up with other ideas and they get scarier as they go.

All's well that ends well, but the best part is that the boggarts aren't done bothering him.  If he has another close up encounter with them, he might even retire...