When a LA quilter charges by the hour, how will they 'prove' to you that they spent XX hours on it? For estimate purposes, it seems much more tangible to quote by the inch. The reason for the 'other' charges you mention is that when you drop a quilt off to a longarmer, it is expected that the top and back are ready to go. If it creates extra work for them, then there are additional charges. There are some who don't like to piece their own backs, so we longarmers will do that for you, but not for free. :) Time is money in any industry. If we take time away from the actual quilting of the quilt, there are costs associated with that time.