Custom Post Type Development

We have a potential project to build a client site that will function as an online recommended book information resource for teachers. The site will operate on a subscription basis, providing access to the online database of several hundred books, that are organised to assist educators in selecting books for classrooms, studies, projects or libraries. The database/resource needs to offer the ability to search, retrieve, browse and list the books by genre, theme, and reader age group depending on what filters the user has chosen. Each book entry will need to include the following:

– Title
– Description
– Author(s)
– Publisher
– ISBN number
– Editions available (eg. hardback, paperback, big book, dual language)
– Cover image (featured?)
– Age range
– Genre
– Links to related titles in database
– Related titled not in database (no link)
– Ability to have/offer attached document(s)/files(s)

The website will not be an e-commerce site, although it will take a payment for subscription, and will function solely as a searchable database/resource. However, additionally we would need to allow the user to somehow build up a several favourites/wishlists within their account that could form the basis of a book order.

We are thinking of two ways to approach this taxk of the book entries;
a) by incorporating additional custom fields into a standard post – not sure how we’d separate the ‘book posts’ from standard blog posts however,
b) by developing a custom post type specifically for the book entries and to keep them separate from regular/standard posts.

We’re thinking that b) would be the smarter way to go, if slightly more expensive to develop. We’re interested to hear what this development, specifically for the custom ‘book post type’ would cost realistically and the development time involved. Or if you have a better suggestion for how we should approach this project.

Also interested to hear suggestions for paid subscription based access plugin that would work well alongside the content being offered.

Has anyone any experience in pulling in additional data relating to a book if you simply have the ISBN number as this would surely speed up the development time?