A photo search comes back with the same silhouette at twenty pounds and at four hundred. That is a normal result rather than a broken one: the search matched on how the garment looks, and how a garment looks is one of the smaller inputs into what it costs.
The useful question is which parts of that gap you can check and which you cannot.
What can you actually verify?
Three things, all on a proper listing.
The fabric composition. Stated as fibres and percentages, and it is the single biggest checkable factor. Natural fibres in fine grades cost more than synthetics, and within a fibre the grade varies a great deal. Merino covers a wide range of qualities. Cashmere is priced by fibre length and thickness as much as by percentage, which is why a garment described as containing cashmere and one described as cashmere are making different claims.
The country of manufacture. Stated on most listings and legally required in some markets. It tells you about the labour cost built into the price, which is one input among several.
The construction, where the copy describes it. Lined or unlined. Canvassed or fused. Whether the seams are finished, whether a pattern is matched across the front, whether the buttons are horn or plastic. Good retailers write this down; poor ones do not, and the absence is itself a signal.
Reading those three takes under a minute and it is the difference between spotting a markdown and buying a different product. The rest of what to read on a listing is in what to check before buying from a result.
What does construction actually cost?
Labour and material, in ways that do not photograph.
Seam finishing. An overlocked seam is fast. A French seam, a flat-felled seam or a bound seam takes longer and uses more fabric. All three look identical from outside the garment.
Lining and interlining. A lined jacket is two garments sewn together. An interlined one has a third layer that gives it structure. Neither is visible from the front.
Pattern matching. Aligning a check or a stripe across a seam wastes fabric, sometimes a lot of it, and takes more cutting time. It is visible if you look at the seams, which nobody does in an outfit photograph.
Number of pattern pieces. A jacket cut from more panels fits better and costs more to make.
Buttonholes and fastenings. Machine-made and hand-finished buttonholes take different amounts of time. Horn, corozo and plastic buttons cost different amounts.
Canvassing, on tailoring. A fully canvassed jacket has a layer of horsehair canvas stitched in that moulds to the wearer. A fused one has it glued. Different products, identical photographs, as covered in finding menswear from a photo.
None of this is in a picture. All of it is in the price. That is the honest answer to why two garments that photograph the same can differ by a factor of ten.
What can you not check at all?
Three things, and they account for a large share of the difference.
Order size. A brand ordering ten thousand units of a garment pays a different unit cost from one ordering three hundred. That is the largest single reason a fast-fashion version of a design is cheaper, and it has nothing to do with how either garment is made.
Cost of selling. Rent on shops, advertising, photography, staff, warehousing, returns handling, payment processing. All of it goes into the price of the garment, and it varies enormously between a brand with high-street stores and one selling direct online.
Positioning. What a brand has decided its clothes are worth. This is a real input and it is not visible anywhere.
The consequence is that price is a poor proxy for quality. It measures the garment plus everything around the garment, and the second part is invisible.
Why do two listings for the identical product differ?
This is a different question from the one above, and it has plainer answers.
Different retailers buy at different volumes and run different margins. Regional pricing means the same product is priced separately for different markets. Sale timing varies, so one shop has marked it down and another has not. Marketplace resellers set their own prices independently of the brand.
All of those produce genuine price differences for the same product, and all of them are legitimate. The full breakdown is in why the same item has different prices, including how to tell a real bargain from a different product wearing the same photograph.
Comparing across retailers is one of the useful side effects of searching across shops rather than within one, and it is worth doing before buying anything that appears in more than one result.
Is the cheaper version worth buying?
It depends entirely on which part of the expensive one you wanted, and that is worth being honest with yourself about.
If what you liked was the shape, the colour and the general look, a cheaper version in a reasonable fabric will give you most of it. That is a good buy and there is nothing wrong with it.
If what you liked was how the fabric fell, how heavy it looked, or how it will look after two years of wear, the cheaper version usually will not deliver, because those are precisely what the price difference paid for. A coat that holds its shape does so because of the cloth weight and the interlining, and a cheaper coat in the same silhouette will not hang the same way.
The way to decide is to look at the composition on both listings and ask whether the difference matters for how you will wear it. A jacket worn twice a year and a coat worn daily through a winter are different purchases even at the same price.
What a dupe actually is covers the line between a legitimate cheaper version and a counterfeit, which is a separate question worth keeping separate.
What does the product copy tell you about the shop?
More than it tells you about the garment, and it is a quick read.
A listing that states the composition, the country of manufacture, the flat measurements per size, the model's height and the size they are wearing, and describes the fit and the fabric weight in words, comes from a retailer who has entered those fields deliberately. That is a shop that knows what it is selling.
A listing with a two-line description, one photograph and no composition is a shop that either does not know or does not want to say. Neither is fatal, and both are worth noticing before you spend money.
The tell that matters most is the composition. It is required on the garment label anyway, so a shop that has not put it on the listing has chosen not to. On a garment where the fabric is the main thing you are paying for, that absence is the answer.
Does the fabric weight matter as much as the fibre?
Often more, and it is stated less often.
Fabric weight is usually given in grams per square metre, and it is the difference between a shirt you can see through and one you cannot, between a coat that hangs and one that flaps, between a t-shirt that lasts a year and one that lasts five.
Two garments in 100 percent cotton can be completely different products because one is a light poplin and the other a heavy twill. The composition line treats them as the same.
Better listings state the weight. Where they do not, the product photographs sometimes show it: a heavy fabric creases in large soft folds, a light one in small sharp ones. That is one of the few construction-adjacent things a photograph does carry, and it is worth looking for when you are comparing two candidates.
The guide on what a garment is made of covers how to read a composition and a weight together.
How does this change how you read results?
Two adjustments.
Treat the price spread as information about your search rather than about the market. A page of results running from a few pounds to several hundred usually means the description was generic, so the search matched a category. Re-cropping narrows it. That is the reading in how to read a shopping result before you tap.
Compare two listings rather than reading one. The differences between two products of the same shape only become visible side by side, and the composition line is where they show up first. Two tabs, thirty seconds.
Snagfit shows where a garment is sold or the closest thing you can actually buy. What those things cost, and why they cost it, is the retailer's to state and yours to read. The search can put the options in front of you and it cannot tell you which one is worth the money.