The 180-listing panic: why I needed a system by Boxing Day
I run a side business flipping electronics, vintage fashion, collectibles and home goods on eBay. In November I bought three house-clearance lots at auction—one in Reading, two in Belfast—and ended up with 180 items to list before the January sales kicked off. I had until 2 January to get them live, because that's when search traffic spikes and people spend their Christmas money.
Listing 180 items the old way—writing each description from scratch, guessing at bullet points, hoping the tone matched the category—would've taken 90 hours. I tried it for the first twelve listings and burned an entire Saturday. The electronics descriptions were too flowery, the vintage dresses read like instruction manuals, and the kitchen appliances just listed features with no reason to care.
I'd been using Claude and Gemini for email drafts, so I wondered: could I build four reusable prompt templates, one per category type, that would let me paste in basic details and get a publish-ready description in under two minutes? And which model would handle each formula without sounding like a robot wrote it?
I tested Claude Sonnet 4.5, Gemini Flash and Llama 3.3 70B across four prompt formulas, ran them against 180 real listings, and tracked which combination gave me the highest view-to-message rate in the first week. Here's what worked.
Prompt formula one: bullet-heavy spec blocks for electronics
Electronics buyers on eBay want specifications first, reassurance second, story never. They're comparing your Canon EOS M50 against four other listings, and they'll bounce in three seconds if they can't find the sensor size or whether the battery charger is included.
This prompt gave me the best results with Claude Sonnet 4.5:
Write an eBay listing description for [item name]. Start with a single sentence overview, then give me a bullet list of specifications (screen size, processor, RAM, storage, condition notes, what's included in the box). End with one paragraph on condition and a line about postage. Tone: factual, confident, no hype. 120 words maximum.
Item details:
[paste your notes here]
I used this for 48 items: cameras, laptops, tablets, a PlayStation 4, a Bose speaker. Claude kept the bullets tight and added condition notes without drama ("Light scuffs on the base, screen is flawless"). Gemini Flash tended to editorialize ("This laptop is perfect for students!"), which tested poorly—electronics buyers distrust enthusiasm. Llama often buried the specs in paragraph form, so I had to reformat.
The Canon EOS M50 listing I wrote with this formula got 340 views in five days and sold for £285, which was £30 above the average completed listing price that week. The buyer messaged to ask about the shutter count; I'd included it in the bullets, so the sale closed in one reply.
Cost per listing with Claude: under 2p at Kryotta's rate. Time: 90 seconds once I'd photographed the item and noted the specs.
Prompt formula two: story-driven vintage and collectibles
Vintage clothing and collectibles sell on narrative. The buyer wants to imagine the piece in their life, or they want to know it's rare enough to justify the price. A 1970s Biba dress isn't just polyester and a zip; it's a piece of London fashion history that'll turn heads at a wedding.
This prompt worked best with Gemini Flash, which has a lighter touch than Claude when you need a bit of romance:
Write an eBay listing for [item name]. Open with one sentence that sets the era and appeal. Then describe the design, fabric, condition and measurements in two short paragraphs. End with styling suggestions or display ideas. Tone: warm, specific, not breathless. 150 words maximum.
Item details:
[paste your notes]
I used this for 52 items: dresses, handbags, vinyl records, a 1980s Casio watch, a set of Penguin paperbacks. Gemini gave me lines like "This midi dress in rust-orange crepe has the wide lapels and belt loops that made Biba a Kensington icon in 1974," which sounded human and moved the item in three days. Claude's versions were accurate but a bit flat; Llama occasionally invented details I hadn't mentioned, so I had to check every output.
The Biba dress sold for £78. The buyer left feedback saying the description matched the item exactly, which matters when you're building a seller rating.
One mistake I made early: I let Gemini write "perfect for a festival" on a 1960s handbag. The buyer returned it because the strap was too short for crossbody wear. Now I edit out styling claims I can't verify, or I make them conditional ("If you prefer a top-handle bag, this works beautifully").
Prompt formula three: spec-focused appliances and home goods
Kitchen appliances, furniture and homeware sit between electronics and collectibles. Buyers want dimensions, power ratings and condition, but they also want to know it'll fit under the worktop or match a magnolia kitchen. The description needs to be practical without being dull.
Claude Sonnet 4.5 handled this best, because it balanced facts with light persuasion:
Write an eBay listing for [item name]. Start with what it is and what it does in one sentence. Then list key specifications (dimensions, capacity, power, material, colour). Add a short paragraph on condition and a line about why it's useful. Tone: helpful, not salesy. 130 words maximum.
Item details:
[paste your notes]
I used this for 44 items: a Nespresso machine, a Dyson vacuum, a set of Le Creuset pans, an IKEA bookcase, a John Lewis desk lamp. Claude wrote things like "This Nespresso Inissia makes espresso in 25 seconds, heats up in 25 seconds, and fits in a 12 cm gap beside your kettle," which answered the two questions every buyer asks: does it work, and will it fit?
Gemini Flash added too much lifestyle fluff ("Imagine your morning coffee ritual elevated"). Llama sometimes missed the dimensions, which led to questions I had to answer manually.
The Dyson V8 sold in two days for £140. The buyer collected it in person, saw it matched the description, and bought a second item from my other listings.
Prompt formula four: benefit-led fashion (non-vintage)
Modern fashion—anything from the last decade—needs a different approach than vintage. The buyer isn't looking for era or rarity; they want to know it'll fit, it's on-trend, and the condition justifies the price. Benefits matter more than story.
This prompt worked well with Llama 3.3 70B, which wrote punchier, more direct copy than Claude or Gemini when I needed speed:
Write an eBay listing for [item name]. Open with the brand, style and key feature (e.g., "Zara high-waisted jeans in mid-blue denim"). Then describe fit, fabric, condition and measurements in two or three short sentences. End with one line on styling or versatility. Tone: straightforward, confident. 110 words maximum.
Item details:
[paste your notes]
I used this for 36 items: Zara jeans, H&M blazers, a North Face jacket, a pair of Dr. Martens boots. Llama gave me clean, fast descriptions that didn't oversell. Claude's versions were fine but slower to generate, and Gemini occasionally drifted into aspirational language that felt off-brand for high-street fashion.
The North Face jacket sold for £62 in four days. The buyer messaged to confirm the pit-to-pit measurement, which I'd included, so the sale closed without friction.
One thing I learned: always include the fabric content if the label is readable. A buyer returned a "cotton" jumper that was 50 per cent acrylic, because I'd guessed instead of checking. Now I write "fabric content not listed" if the label is missing, and I've had zero returns since.
Which model per formula: speed, cost and tone
- Electronics (bullet-heavy specs): Claude Sonnet 4.5. Fastest at structured output, fewest edits needed. Cost: ~2p per listing.
- Vintage and collectibles (story-driven): Gemini Flash. Best at warm, specific narrative without sounding like a Pinterest caption. Cost: ~1p per listing.
- Appliances and home goods (spec + benefit): Claude Sonnet 4.5. Balanced facts and light persuasion. Cost: ~2p per listing.
- Modern fashion (benefit-led): Llama 3.3 70B. Punchy, direct, no fluff. Cost: under 1p per listing.
Total cost for 180 listings: under £3. Total time: about six hours, including photography and uploading. I listed everything by 30 December, and by 7 January I'd sold 91 items for a combined £6,340. The view-to-message rate was 8.2 per cent, which is above my usual 5.9 per cent, and I had four returns instead of my normal twelve.
The biggest time-saver wasn't the writing—it was the consistency. Every listing in a category followed the same structure, so buyers knew what to expect, and I didn't waste time deciding how much detail to include. I also tested each formula on five listings before scaling up, which caught the "perfect for a festival" mistake early.
What didn't work (and what I'd change next time)
I tried a fifth formula for books—opening with a quote from a review, then a plot summary—but it added 40 seconds per listing and didn't improve the sell-through rate. Books sold just as fast with a two-sentence description and the ISBN.
I also tried letting the models write the listing title, but eBay's search algorithm rewards keyword density over readability, so I went back to writing titles manually: "Canon EOS M50 Mirrorless Camera Body Only Black Boxed Charger Strap."
One regret: I didn't track which listings got the most watchers in the first 24 hours, which would've told me if one formula was better at capturing intent. Next time I'll pull that data from eBay's seller hub and adjust the prompts accordingly.
If you're listing into the EU, remember that distance-selling VAT rules apply if you're over the £8,818 threshold (€10,000). I'm not there yet, but I've built a spreadsheet to track it, because hitting the threshold mid-year is a nightmare.
Questions people ask
Can I use these prompts for Depop or Vinted?
Yes, but shorten them. Depop buyers skim on mobile, so cut each formula to 80 words and front-load the key detail (brand, size, condition). Vinted is even terser—one paragraph, no bullets.
Which model is cheapest if I'm listing thousands of items?
Llama 3.3 70B and Gemini Flash are both under 1p per listing at Kryotta's rates. If you're doing volume, test Gemini Flash first; it's fast and the output rarely needs editing.
Do I need to fact-check every AI-generated description?
Yes. I caught Llama inventing a "leather trim" on a handbag that was entirely canvas, and Gemini once wrote "never worn" when I'd noted light sole wear. Always compare the output to your notes before you publish.
How do I stop the descriptions sounding samey after 50 listings?
Rotate two or three variations of each formula. For electronics, one version can open with the brand and model, another with the key feature ("24.1 megapixel APS-C sensor"). For vintage, vary whether you lead with era, designer or styling. The structure stays the same; the hook changes.
I've listed another 60 items since January using these four formulas, and the process still takes under two minutes per listing. If you're facing a similar backlog—or you just want your eBay descriptions to sound less like you wrote them at midnight—try one formula on five listings, check the results, then scale up. You can test all four models and compare output side-by-side at Kryotta; I keep a workspace for each category so I don't lose the prompts.
