Black Hollow by Robbie Cox

A sister lost and a paranormal bank threatened with collapse.
Kerry Underwood begged her sister not to take the job in Black Hollow. Now, her sister's missing, and Kerry must go to the community she can't even find on a map in search of her. However, Black Hollow is nothing like she expected, and she fears the truth of a real paranormal town put her sister in danger. To make matters worse, the rugged bank manager who lured her sister to Black Hollow keeps stonewalling Kerry, keeping the answers she desperately needs close to his powerful chest.
Arden McCarthy, leprechaun and bank manager at The End of the Rainbow Savings & Trust, is in a desperate hunt to uncover the threat to his bank's funding. However, the private investigator he hired to ferret out the culprit has vanished along with any leads she uncovered. To complicate matters, the investigator's sister arrived in Black Hollow and keeps sticking her nose in his business.
Frustrated with the mysterious leprechaun, Kerry resists her desire for Arden, while fearing he's weaving his way into her heart.