Another Heaven — Renee Roszel

They had another prize in mind

The mistress of Barren Heath Isle was dead. The new owner would be whichever relative could solve the puzzle she'd left behind. And so began the bizarre invasion of Barren Heath, launching a treasure hunt that led Rule Danforth straight to Mandy McRae.

As the resident landscape architect, she was invaluable to him--she knew all the island's nooks and crannies. And because his motives were so noble--and his rugged looks so appealing--Mandy made him a deal .... But very soon the intrepid pair found themselves seeking out secret places that had very little to do with buried treasure .. ..