A price is a single number; a cost is the explanation of that number. In most workshops the price is known but what sits underneath it is not: how much is material, how much is processing, how much space is taken by waste. When that breakdown is not visible the price turns into a guess, and some jobs turn out to carry no margin.
What a glass costing system does is separate those lines. The area comes from the measurement; the material cost from the price list; processes such as edging and tempering are added onto the line. Because each is its own row, it becomes visible which line is driving the total.
The waste line is usually the one skipped, and it is the most expensive thing to skip. Once the cutting plan is produced it is clear how much of the sheet was used; if the unused part is not written anywhere the cost looks lower than it is. When the plan and the cost feed from the same record this falls into place by itself.
Offcuts entering the arithmetic earns its place here too. A usable piece from a cut, once recorded in inventory, becomes material that has already been paid for; when it is used on the next job that job comes out cheaper. Without an offcut record this gain is invisible, because there is nothing to measure.
The real benefit here is not a report but a habit. If the cost lines are visible on every quotation, nobody has to guess while giving a price. A glass pricing system says which list the price came from; a costing system says how much of that price is material.
Cost changing over time enters the record too. If the same glass was bought at a different figure six months ago, the cost of past jobs stands at that day's number. Recalculating the past with today's price means showing the past incorrectly; the record does not do that, and comparisons stay on honest ground.
At the end of the chain there is still one record. A glass quotation system turns an approved quotation into an order and a customer account system derives the balance from it. That is what is meant by a quotation system for glass workshops: quotation, cost, order and account all speak the same number, and that number is never typed a second time.