It's the modern scourge: the fast-paced upgrade cycle for tech products means we all tend to get a new phone well before we really need one, and it's the same for tablets and plenty of other gadgets.

They're still worth money, so there's no point in stuffing them at the back of a drawer: post them online and sell them quick. There are various apps and websites you can use to get rid of your unwanted kit (it doesn't have to be tech of course - it could be anything).

Gumtree + Shpock

These two websites, which also offer apps for Android and iOS, are a good option.

They both offer a free and easy way to list something for sale. And it's completely free.

Set an appropriate price for your item (slightly higher than you actually want) and expect buyers to haggle.

They may haggle via the service before they come to see it, but may also knock you down based on their inspection when they arrive.

The disadvantages with Gumtree and Shpock is that you have to meet buyers face to face, which some people don't like. There's also risk involved with accepting cash: make sure you check the notes you've been given as neither service offers any security and it is possible to get conned. Definitely don't post any items to buyers and expect them to pay once they receive them!

How to sell online

Facebook

Yep, you can now list stuff for sale in the Facebook app. Tap the little house icon (middle-top on Android and middle-bottom on iOS). This displays the marketplace feed where you can see what people are selling locally.

To list something type in the 'What are you selling' box (above right in the image) and add photos from your camera roll. It's that simple. But the same disadvantages apply as for Gumtree and Shpock.

eBay

If you don't want people coming to your house then list your stuff on eBay. You'll be advertising the item to millions of people so you're likely to find a buyer quickly. Consider listing as Buy it Now if you want to make sure you get a certain price, but more people will be inclined to bid if you use the auction format and use a low starting price.

The down side is that eBay will take a chunk of the money and then PayPal takes another cut (and this also applies to postage costs, annoyingly). 

Do read our 30 tips and tricks for making more money on ebay.

Amazon

Like ebay, Amazon also allows anyone to sell on its platform. It calls them 'Marketplace sellers' and you can expect Amazon to take around 30 percent of the total for the privilege. 

It's simpler to list items though, as in most cases Amazon will already sell the product so you can just choose whether to undercut everyone else selling that item, which is the quickest way to shift something. 

For used items, Amazon offers a grading system and you can describe its condition too. To get started selling on Amazon, head to Seller central, or click a 'Sell on Amazon' next to the 'Have one to sell?' link beneath a product's price.

How to sell online Amazon

Trade-in

It's fairly niche but Amazon offers a Trade-In service for books and video games. Simply search for the item you have and in the bottom corner of the page should be a box offering you an exchange for a gift card. The postage is free and you can even drop items off at a post office or local pickup point like newsagents.  

Sell to a shop

One option is to sell your item (depending on what it is) to shop. High-street stores such as CEX, Cash Converters and Cash Generator will buy things from you. You might not get a great price for it, but it's worth a look and you can often check how much you'll be offered on their websites first.

If you're trying to sell a phone or tablet there are specific sites. Find out more in our separate guide on how to sell your phone.

Sites such as MusicMagPie and Zapper will buy electricals, but also other items such as CDs, DVDs, video games and books - even Lego.

Sell to a friend

An easy option is to sell to someone you know (friend, family member or colleague). It's the simplest method with the fewest complications and almost nothing can go wrong. That's assuming what you have to sell is fully working, or you're totally upfront about any defects, whether cosmetic or functional.

Apple products

Head to mResell, and enter your serial number for a quick and easy way to get a good price on all Apple products .

See also: How to make extra money online.