Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Inaccurate and unreliable source.

I bought this in order to estimate the vaule of my collection for insurance puposes and wasted my money. The guide claims that, for example, my mono Jackie McLean "Destination Out" is worth $30. If I were to lose my copy due to fire or some other reason would I be able to find another copy for $30? Absolutely not. More like $60. Several listings are completely out of touch with the current market and subsequent repressings of older recordings are overpriced. If you really had no idea about the jazz LP market then this book will be of at least some help. You might be cheating yourself, however, if you are looking to appraise a jazz collection about which are are unfamiliar.