1. Read the offer as it is
First rule: retype nothing. Every re-entry adds its own errors to the supplier's. Start from the file you received, or the message as it came, and give every line the same fields: reference, description, colour, price, currency, incoterm, pack size, barcode.
Keep, for every line, the file and the row it came from, and date the offer. An undated offer compares with nothing, and a line without an origin cannot be checked.
2. Work out the landed cost of every line
The supplier price is not the purchase price. For every line, convert with your rate, add fees, customs duty and freight according to the incoterm: that is the landed cost, what the unit costs you once it is with you. Our landed cost calculator shows every step.
Beware of defaults. Freight applied “for want of better” to a small item can skew everything: in a real offer, a 2 GB SD card filed by default in a size class that was far too big had its landed cost overstated by 104 %. A default is not a fault; keeping quiet about it is.
3. Check the unit can be sold on
A cheap unit that does not sell is not a bargain. The benchmark is the public price: what the end customer pays in a shop. Between that price and your landed cost, your reseller customer has to keep their margin. Hence a ceiling:
Reseller ceiling = public price incl. VAT ÷ 1.2 × 0.77
The price excluding 20 % VAT, minus 23 % left to the reseller. Headphones on the shelf at €89.99 give a ceiling of €57.74.
The verdict then reads line by line:
- Viable the landed cost is under the ceiling, with room for your margin.
- Tight it fits, but the margin left falls below 6 %: negotiate before you order.
- Not viable the landed cost is above the ceiling, or the minimum margin per unit does not fit under it.
- No benchmark no reliable public price: the landed cost is worked out, resale cannot be checked.
That last case matters more than it seems. In two real offers, 33 lines came out “viable” when not one of the 24 references had a public price on record: a verdict without a benchmark is not a verdict. For the public price, Merconto keeps the median of the five cheapest new offers on Google Shopping, and publishes nothing below five merchants (Pro and Business plans, and during the trial).
4. Look for errors in the list
Price lists contain errors, and not just a few. Going through three real offers by hand, before writing a line of code, Merconto's founder found nine kinds, including a 45 % gap on the same reference between two suppliers. Here is what to look for:
| What to look for | Why it matters |
|---|---|
| Missing currency | a price without a currency means nothing: 100 in dollars or in pounds is not the same price. |
| Missing or wrong barcode | without a valid EAN, the reference does not match other offers and its public price cannot be found. |
| One EAN, two products | seen in a real offer: a 64 GB and a 128 GB USB drive under the same code. One inherits the other's public price. |
| Copied price | two different models, one under the other, at the same price: often a supplier copy-paste. |
| Colour priced out of line | the same model dearer in blue than in black, by more than 5 %: a question to ask. |
| Range out of line | a smaller capacity dearer than a bigger one in the same range: the 128 GB above the 256 GB. |
| Sales restriction | “not for EU”, “export only”: a line you may not sell in your territory. |
| Different pack size | unit, pack or carton: two offers that do not compare unit for unit. |
| Gap between suppliers | the same reference more than 5 % dearer than elsewhere, once everything is in euros. |
| Above the market | a landed cost above the reseller ceiling: the line cannot be sold on. |
| Two versions that differ | between the initial list and the list received: a price appearing in an empty cell, an amount changed, a restriction gone. |
One rule above all: flag, never correct in silence. Correcting a doubtful line yourself swaps an error for an assumption. The line gets flagged, and checked with the supplier. And no alert for nothing: a few per cent between two colours is a batch or an exchange rate effect, not an inconsistency. A false alarm wears out the attention the real ones need.
5. Decide, line by line
An offer is neither taken nor refused as a block. Sort the lines by verdict: order the viable ones, negotiate the tight ones, ask your questions on the flagged lines, and see whether another supplier sells the non-viable ones for less. The guide on comparing supplier price lists covers that last step.
Which currency for the lines without one? Which barcode for row 17? Why is this colour dearer? Does this “export only” note apply to your country? For what quantity is this price valid, and until when?