I'm not marketing genius, but shouldn't it be a better plan to make your book easy for potential readers to access instead of really hard?
"But Mr Dent, the plans have been available in the local planning office for the last nine months."
"Oh yes, well as soon as I heard I went straight round to see them, yesterday afternoon. You hadn't exactly gone out of your way to call attention to them, had you? I mean, like actually telling anybody or anything."
"But the plans were on display ..."
"On display? I eventually had to go down to the cellar to find them."
"That's the display department."
"With a flashlight."
"Ah, well the lights had probably gone."
"So had the stairs."
"But look, you found the notice didn't you?"
"Yes," said Arthur, "yes I did. It was on display in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying 'Beware of the Leopard'."