house book rule
If you don't like the listed version, try this: (I don't have my books here, so someone will do the math). Figure out the cost of a wondrous item that has endure elements (1st level caster) and reduce (? level caster) as permanent effects. This book has the dimensions and durability of Boccob's Book listed above, and works otherwise as a normal spell book (50 spell levels, pay to inscribe). You could up the price and charge nothing for inscribing the spells, but that seems pointless, though not unbalancing.
If you don't like the listed version, try this: (I don't have my books here, so someone will do the math). Figure out the cost of a wondrous item that has endure elements (1st level caster) and reduce (? level caster) as permanent effects. This book has the dimensions and durability of Boccob's Book listed above, and works otherwise as a normal spell book (50 spell levels, pay to inscribe). You could up the price and charge nothing for inscribing the spells, but that seems pointless, though not unbalancing.