The Ferret Has Landed

Gormless Sebastian Avon has graduated with a BA in nothing useful whatsoever and returned home to his family to contemplate his future and his navel. When he falls in love with the new neighbours' talentless interior designer - aka The Ferret - his parents and four younger brothers are horrified. But Seb is smitten and cannot see what a ghastly girl she is.
Over the field in Brothel House, what skeletons are hiding in the Fanshaw-Browns' cupboards? Archie F-B claims to be a world famous author, so how is it no one has ever heard of him or even seen one of his books on a shelf?
The Avons appear to be the only ones who are who they say they are in a tale of murder, forgotten crimes and buried treasure.