Each guide explains what actually moves the price in one collecting field: the makers and marks worth checking, how condition and restoration change the figure, which selling routes suit which pieces, and the realised auction and dealer prices behind the ranges. Every guide links to real valuation reports from the same field, each with its cited comparable sales.
New guides are added as reports in each field accumulate. If your piece belongs to a field without a guide yet, the valuation itself still covers it: upload photos and the report comes back with the same cited comparable sales, condition notes and confidence level. The first valuation is free. See the example reports or start with a free valuation.