You know that conventional wisdom about how you'll succeed in business if you identify a gap in the market, something people need and may not even know they need, and then fill it? That's what Vendoo, an app that helps you crosspost sales listings across multiple reselling platforms, does. Manually listing your wares on eBay, Mercari, Poshmark, Vestiaire Collective, and whatever else is tiresome and tedious, so you'd be forgiven if you just picked one resale app and stuck to it. But Vendoo, available on the web, iOS, and Android, releases you from that limitation. You do still have to put a smidge of work in, but it's significantly less work than you'd be doing if you tried to cross-list on your own, and makes it much easier to maximize profits by casting as wide a net as possible.

Vendoo enables you to cross-list your available products across multiple resale platforms, letting you post the same listing in all of them at the same time, without forcing you to create individual listings in each platform one-by-one. So, instead of opening Poshmark and making a listing for something, then opening Mercari and making a listing the same thing, then opening Depop... you get it. Instead of that, you make one listing in Vendoo and then share it to all of the platforms you use. Vendoo supports eBay, Etsy, Poshmark, Mercari, Grailed, Depop, Vestiaire Collective, Vinted, Facebook Marketplace, Shopify, and Whatnot.

It also functions as an inventory management tool, allowing you to see all the items you have for sale, what you have them listed for, where you have each listed, and more. You can sort your inventory all kinds of ways, from newest to oldest, to date modified, to least active. You can also sort by price, by name, or by SKU. A lot of those features are, understandably, for heavy hitters, like people who manage small boutiques or actually make a living reselling, but they're plenty useful for the average closet-clearer, too, provided you have some volume to offload. I only sell clothes to make money to buy new clothes (which I will wear and then sell). I'm not a professional by any means, but I enjoy this as a hobby and a way to keep my wardrobe fresh. It's helpful to be able to sort my inventory so I can see which items are getting attention, which could stand to go on sale, and which have been up for sale for so long that I might as well just donate them.

Finally, this app can also track your sales and generate reports for you so you can monitor how you're doing across the platforms you sell on. Most platforms, like Poshmark, also generate app-specific analytics for you, but here, you get a comparison that gives you enough insight to help you make decisions about where to focus your energy. Depop sales down? Run some discounts. Vestiaire Collective sales up? Your stuff is in high demand, so add some more. Poshmark buyers are particularly interested in a certain brand? Raise the prices of the brand just a little bit on the app.

Vendoo also automatically detects sales on a given platform and flags them to you so you can delist the sold item everywhere else. One thing I'd like to see from Vendoo is automatic delisting on sold items as a free feature, though. A while back, while I was using a free version, I sold a sunglasses case overnight on Poshmark and didn't notice until the morning, but its listing was still active on my Depop when I looked. The likelihood of someone trying to buy it even though it wasn't available anymore was low, but not nonexistent (if someone did, I would just have to cancel it, so no biggie, but I'd still rather avoid this). I had to log into my Depop to delist it manually, as delisting -- automatic or manual -- is a paid feature on Vendoo (more on that in a bit).

To give you an idea of how easy it is to make a listing on Vendoo, let me walk you through it. When you open the app, you see your inventory, as well as a search bar at the top and a menu on the bottom. The menu has tabs for inventory management, sending offers to potential buyers, selling items, importing items, and accessing your settings. Hit Item in the center and you'll see a screen called "new item." If you're familiar with listing on any of the various platforms, this will be pretty familiar to you: You start by adding photos, then a title and a description. Choose the brand by typing it in and selecting it from a menu. The next inputs are for condition, primary and secondary color, SKU, your zip code, relevant and searchable tags, and the quantity you have available. Enter the category (like women > accessories > sunglasses) and size, package weight, listing price, and original retail price. You can even enter in info buyers won't see, to keep yourself more organized. These include Vendoo labels (tags) and internal notes, so if, for instance, something is in a storage locker and you might not be able to ship it for a few days, you could jot that down in there.

You'll see two buttons at the end. The first is Create and the second is Marketplaces. You can't put a listing into your marketplaces until you create it, so hit that one first. After that, any time you open the listing, you can go straight to the second button to see where you have the item listed or list it on a new platform.

The item will appear in your inventory, be searchable and trackable, and push to whichever marketplaces you select.

Something I appreciate about Vendoo is that it's constantly innovating to make the user experience better. Some apps I use to help me out with my various projects and endeavors, like AI Measure, don't ever really change; they just are what they are. For instance, Vendoo just rolled out the ability to add videos to listings, which can then be posted to Poshmark or eBay. I do upload videos to my Poshmark listings pretty frequently, especially if the item is glittery, has another unique feature, or has some damage, but I have to do this manually within the Poshmark listing itself because videos aren't supported on Vendoo -- or at least, they weren't. Now, you just throw them in with the pictures and you're good. This only works with an annual or monthly unlimited subscription, which we'll get to. I don't care to pay for the unlimited plan every month, so for now, I'm still manually uploading any of my necessary videos, but I am impressed that this feature exists, and the app is clearly continuing to innovate to meet sellers' needs.

After some trial and error, I have a few tips for using Vendoo. First, it works much better if you create the listing for an item within Vendoo, then share it everywhere, rather than creating the listing in a particular resale app, importing into Vendoo, and listing elsewhere. When you create a product in Vendoo, it asks you all the questions you'd need to answer on any app, like size, category, weight, and shipping origin. Not every app wants the same details in listings, though, so importing could leave you having to do some extra work on Vendoo that you'd already have taken care of if you started there. Depop, for instance, doesn't put titles on listings, whereas Poshmark does. Mercari and Depop need you to select your address as the origin and won't let you list until you do, but Poshmark doesn't make you do that. Vendoo asks you all the questions any app could possibly need upfront, making it very easy to then duplicate that listing across all your platforms. You may end up filling in fields you don't end up needing, but it's better than redoing all your listings if you don't fill in fields you need.

Of course, just starting out on Vendoo probably means you already have a bunch of listings on one platform already, and in that case, it could be worth it to import those into your Vendoo inventory instead of remaking each listing from scratch within Vendoo. That's what I did with all my Poshmark listings, but I'll caution you that there's another downside to importing -- it's a paid feature. If that doesn't scare you away, though, I suggest importing on a computer, ideally using the app's Chrome extension, because it can cause your phone to lag. Honestly, I prefer to use the computer for most things, so I cross-posted all my Poshmark listings to Depop and Mercari that way, too, instead of using my phone after everything was in my Vendoo inventory. But it's up to you which interface you prefer.

Finally, make sure you're uploading your listings to the right account on each app. By accident, I have two Depop accounts: One is tied to my Gmail account and the other is tied to my iCloud account. Reader, I still don't even know how this happened, but one account is a decade old and the other is pretty new. On my phone, I'm logged into the iCloud one and on my computer, unbeknownst to me, I was logged into my Gmail one. Because so many sellers wheel and deal across not only multiple platforms, but multiple, curated accounts, Vendoo (reasonably) assumes that whatever account you're logged into on the device you're using is the account you want to list on -- which is how I ended up accidentally putting eight listings on the Gmail-associated account while I cross-posted from my computer last night. I wanted to sell these via my iCloud account instead, and while I was able to delist them on Depop, my Vendoo account still considered them "listed."

While I couldn't delist these from other storefronts using Vendoo, I did have a solution, but it was a bit of a pain and did take up some of my sales slots for that month (more on that later). To rectify my whole situation, I had to delete all of my incorrect listings from my Vendoo inventory altogether (a separate process from delisting, since it's free but won't remove listings from storefronts for you). Then, I had to reimport from Poshmark and relist the items I wanted to sell to the right Depop. These new imports did count against my total number of allowed imports/inventory slots for that month, as the deletion didn't free up any of this month's slots, but at least I didn't have the pointless listings stuck in my inventory anymore. This entire debacle was my fault, but still annoying. Learn from my mistake.

You have to pay to use most of Vendoo's features, but how much you'll pay and what you'll pay for will depend on your needs. For free, you can create and cross-list five new items per month and remove the backgrounds from three product images. (A lot of sellers like to upload photos with no background, but I find this tedious and silly. I only do it if my apartment is a mess and you can see it in my pictures, but I also use a free site like Remove.bg for that. Hell, your iPhone can do it for you for free, so don't let the background-removal features sway you toward paying if you're on the fence.)

For $9 per month, you can create and cross-list 25 new items per month and remove 25 backgrounds. $20 per month will let you create and cross-list 125 new items that month, $30 per month will get you 250 that month, and $50 per month will get you 600 that month. For unlimited creations/cross-listings, you need to pay $70 per month, which is also the tier that will unlock adding videos to Poshmark and eBay. Within each of these tiers, however, you have more feature and payment options.

Additional add-ons are $5 per month and include the ability to import listings from one of your sales platforms to your Vendoo inventory (which counts toward your monthly allotment of items), the ability to relist and delist multiple items across storefronts, and the ability to list your wares in up to 10 marketplaces. Without that last add-on, you're capped at three platforms. You can put all the add-ons into your monthly subscription for an additional $12 on top of what you're paying for your inventory allowance.

Each month, you'll have to pay again to create or import more items, which I appreciate. If I have a lot to sell, I can spend more to list all the goods, but when I have less to sell, I don't need to fork over all that cash. The payment isn't for the storage space, but for the option to create or import, so even if you only have 50 things in your inventory and paid for 125 for the month, you'll need to pay again the next month if you want to add more than five new things. Any unused creation or import slots do not roll over and an item's sale or deletion does not restore its slot. On the plus side, this means your inventory can be as big as you want or need it to be, so you can keep listings you created the previous month active.

So, hypothetically, you could use the free version if you only want to create five new listings a month, though you won't be able to import those from an existing marketplace without paying, nor will you be able to share them to more than three marketplaces without paying. If you don't sell much, that could be enough, but in my opinion, even as a very casual seller, it's worth it to pay.