So, down to the nitty gritty ...
1) Is this book 'desirable'?
Often booklets or self published books were limited print runs. But, if no one wants the book then just because a book was a limited run, doesn't make it worth a vast amount of money.
In the book blog, I've annotated each entry as to whether or not it's still in print. If you can't find the book that you are looking for then remember, it's a work in progress. Fill out my contact form with details of the book and if I have it in the library I'll push the entry to the top of the list for you.
2) Is this book still in print?
3) What is this book worth?
Some books though, remain very highly priced regardless of trends.
And finally ...
If the book has prickings in it on a separate sheet, always confirm whether or not that sheet is included. Nothing worse than buying a book to find out you can't make the patterns because they are missing.
From time to time I post on different groups and wanted to collect some of the advice that I give in one places.