Comparing supplier quotes with AI: separate unit price from order cost
Compare supplier quotes with AI by separating per-piece price from order cost and keeping the original terms.
Key points
- Keep each quote's price and unit
- Show order cost; per-piece is a guide
- Ask the supplier; don't let AI fill gaps
Overview diagram in preparation
Contents
Keep each quote's original price and unit in the table
A&A perspective
An AI supplier-quote comparison table is one where you have AI read each supplier's quote and line up the prices for the same product side by side. The first thing to keep in it is the price and unit exactly as the quote states them. If a quote says "¥4,800 per box (24 pieces)", put that wording in one column, unchanged.
A&A perspective
A table showing only per-piece figures that AI has worked out loses how the item was originally sold: by the box or one piece at a time. Later, when you ask "Can I buy 30 pieces at this unit price?", you have nothing to check it against.
From the sources
Google Workspace, Google's business service, includes an AI called Gemini. According to its help page, you can give Gemini several files as sources and have it compare data across them. Below an answer, you can see a list of the files used for it.
From the sources
The same help page says that even when sources are shown, Gemini can be wrong. It may leave out a source it used, cite a document that was not directly used for that answer, or make up a source. It asks users to verify the answer with the listed sources, and with other sources they trust, before relying on it.
A&A perspective
Automate & Augment (A&A), which writes this article, reads this as meaning that you should check the figures in an AI comparison table against the original quotes before using them. If the table keeps each quote's price and unit as written, you can see right away what to compare when you open the source file.
Hypothetical example
For example, suppose a six-person wholesale company selling sundry goods wants to buy 30 paper bags. Three quotes arrive. Supplier A quotes "¥4,800 per box (24 pieces), sold by the box", Supplier B quotes "¥210 per piece, minimum order 50 pieces", and Supplier C quotes "¥21,600 per case (a case holds 10 boxes of 12 pieces each)". The company names and the numbers are fictional, made up for this article.
A&A perspective
When you ask AI for the comparison table, put this in the instruction: "Copy the price and unit written in each quote into the first column, without rewording them." Once the table is made, open the three quotes and check them against the first column.
Separate the per-piece figure from what you can order
A&A perspective
The per-piece unit price is a reference figure for comparing suppliers; it does not necessarily mean you can buy at that price. Put what you would actually pay for the quantity you are ordering in a separate column.
From the sources
Microsoft's documentation for Dynamics 365, its business system, has an article on how prices are handled when the unit on an order changes. It explains that the system takes the price from a trade agreement with a supplier or similar settings, and that each price is set for a particular unit.
From the sources
When the unit on an order line is changed, the system looks for the price set for the new unit and applies it. If none is found, it applies no price. The article says that unit conversion cannot be used to recalculate the price in another unit. The workaround it gives is to set up a price agreement for each unit you expect to order in.
A&A perspective
A&A reads this as saying that the price of a box and the price of one piece are set separately. This business system does not work out the price of one piece by dividing the price of a box by the number of pieces in it. The per-piece figure that AI works out by division is likewise only a guide for comparison. It does not mean you can buy a single piece at that price.
Hypothetical example
Converting the earlier example to per-piece prices gives ¥200 for Supplier A, ¥210 for Supplier B and ¥180 for Supplier C. Cheapest first, the ranking is C, A, B.
Hypothetical example
If you instead calculate with the quantities you can actually order to get the 30 pieces you need, the ranking changes. Supplier A is 2 boxes, 48 pieces, ¥9,600. Supplier B is the minimum order of 50 pieces, ¥10,500. Supplier C is one case of 120 pieces, ¥21,600. You pay least with A and most with C.
A&A perspective
Ranking by per-piece price and ranking by what you pay for this order can come out in a different order. So alongside the per-piece column, the table needs a column for the quantity ordered and the number left over, and one for the amount paid. If the surplus is a consumable you can use later, picking the lower per-piece price can also make sense. The owner decides which to choose. This table does not compare tax or shipping.
| Comparison table column | What to write | Example row for Supplier C |
|---|---|---|
| Quote as written | Copy the price and unit in the quote without rewording | ¥21,600 per case (a case holds 10 boxes of 12 pieces each) |
| Per piece (reference) | A guide only: the quoted price divided by the number of pieces included | ¥180 |
| Quantity to order and surplus | A quantity that covers what you need, in a unit the quote lets you buy | 1 case, 120 pieces (pieces beyond the 30 you need are left over) |
| Amount paid | What you pay for the quantity ordered | ¥21,600 if bought by the case; blank if bought by the box |
| To confirm | Terms the quote does not state, written as a question | Can we order a single box of 12? If so, at what price? |
Ask the supplier to fill terms the quote leaves out
A&A perspective
Do not let AI guess at terms the quote does not state; have it put them in a column called "To confirm". Do not choose that supplier until you have asked and received an answer.
Hypothetical example
Supplier C's quote in the earlier example says that the case holds 10 boxes of 12 pieces each. It does not say whether you can buy a single box, or at what price.
Hypothetical example
Suppose AI fills the gap by dividing the case price by 10 and writes "¥2,160 per box". If you then calculate buying as many boxes as you need at that figure, Supplier C looks cheapest on what you pay this time as well. But that figure appears nowhere in the quote.
A&A perspective
As the previous section showed, A&A treats prices for different units as separately set values.
A&A perspective
Put this in the instruction to AI: "Leave blank any price or term not written in the quote, and write it as a question in the To confirm column." For Supplier C's row, the To confirm column then shows "Can we order a single box of 12? If so, at what price?"
A&A perspective
You can send a question from the To confirm column to the supplier as it is. When a reply comes, copy the supplier's answer into the Quote as written column and add the date you received it. Until the reply comes, leave blank what you would pay for buying boxes from Supplier C. The ¥21,600 for buying by the case is stated in the quote, so keep it in the table.
A&A perspective
Handle a minimum order quantity or a sold-by-the-box restriction the same way if the quote does not state one. A restriction that is not written down is not the same as no restriction.
A&A perspective
The table below shows example comparison-table columns and how to fill in Supplier C's row.
Summary
A&A perspective
Keep each quote's price and unit as written in the comparison table. Open the source files AI shows and check them against the Quote as written column.
A&A perspective
Make the per-piece conversion a reference column, and show the quantity ordered, the number left over and the amount paid in separate columns. Ranking by per-piece price and ranking by what you pay for this order can come out in a different order.
A&A perspective
Do not let AI fill in terms the quote does not contain; have it list them as questions in the To confirm column. Do not choose a supplier on that row until the supplier's answer arrives.
The per-piece unit price in an AI comparison table is a guide for comparing suppliers. Keep each quote's price and unit as written, and show the quantity ordered, the number left over and the amount paid in separate columns. Ask the supplier about any terms the quote lacks, listed under To confirm, and choose where to order after the answer arrives.
FAQ
Is it a mistake to ask AI to compare by per-piece unit price?
It is not a mistake. A per-piece unit price is a guide for comparing suppliers. But that price does not necessarily mean you can buy the quantity you need at that price, so keep it as a reference column and put it beside a column for what you pay for this order.
Should I include tax and shipping in the comparison?
The comparison table in this article compares only the unit and quantity conditions for buying the same product. Check the total with tax, shipping and payment terms separately. The approach stays the same even then: keep each quote's terms as written, and have AI leave unwritten terms blank and list them in the To confirm column.
Is it the same if I make the comparison table with ChatGPT or Claude instead of Gemini?
The sources for this article are two: Google's help page and Microsoft's documentation. This article has not checked whether the same cautions appear for other AI tools. A&A considers that using separate columns for the quote as written and the items to confirm works whichever AI you ask.
Sources & editorial note
Primary pages read for this article. Publication dates below belong to the sources; access dates record our research.
- Learn how to use sources with Google Workspace with Gemini
Google Drive Help · Not shown on the page
Accessed 2026-11-04 - Unit prices on purchase orders aren't calculated based on the unit conversion
Microsoft Learn · Last updated on 2024-05-16
Accessed 2026-11-04