Tiles and Tribulations by Tamar Myers (2003, Paperback)

Abigail Timberlake Washburn would rather be anywhere else on a muggy Charleston summer evening -- even putting in extra hours at her antiques shop -- than at a séance. But her best friend, "Calamity Jane," thinks a spirit -- or "Apparition American," as ectoplasmically-correct Abby puts it -- lurks in the eighteenth-century Georgian mansion, complete with priceless, seventeenth-century Portuguese kitchen tiles, that C.J. just bought as a fixer-upper. Luckily, Abby's mama located a psychic in the yellow pages -- a certain Madame Woo-Woo -- and, together with a motley group of feisty retirees known as the "Heavenly Hustlers," they all get down to give an unwanted spook the heave-ho. But, for all her extrasensory abilities, the Madame didn't foresee that she, herself, would be forced over to the other side prematurely. Suddenly Abby fears there's more than a specter haunting C.J. And they'd better exorcise a flesh-and-blood killer fast before the recently departed Woo-Woo gets company.