The advent of online marketplaces, led by eBay nearly 20 years ago, has become a boon for small businesses. Whether they're brick-and-mortar stores or single entrepreneurs operating from home, sellers around the world have been aided in finding customers as never before. New niche marketplaces, as exemplified by Etsy, are bringing exciting new opportunities for growing businesses.

As the popularity of online marketplaces increase, small business owners and online shop creators may find it harder to stand out in the crowd. Customers are more knowledgeable and higher-quality goods are being sold online.

To overcome these challenges, follow these five best practices to make the business and its products stand out in a competitive environment:

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1. Take great (and unique) photos. High-quality photography is critical. Airbnb, one of the best-known online marketplaces, relies on professional photography

For product photography, many experts endorse plain white backgrounds with detailed shots of each item. In fact, Amazon recently received a patent on a very particular setup for its take on white-background photography. As ridiculous as that patent may seem, it shows how critical photography has become when listing products online.

While white backgrounds can make a listing look professional, this factor on its own does not amount to a particularly distinctive aesthetic, so a photo with just this characteristic might not stand out against the competition. A more unique photography style -- used consistently for all products -- will make images instantly recognizable. The listings will look more professional and leave a lasting impression on customers.

Use as much “negative space” around each image as possible since this makes it easier for the site to spotlight the content in marketing efforts.

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2. Tell a story. To build an identifiable brand, company owners need to tell stories, for example, why they started a business, what are the brand's values, what was the owner's inspiration. Most online marketplaces will let companies create homepages to post corporate  information, photos and videos. That’s where the story should start.

Next, tell a story for each individual listing. Why is a particular product meaningful? What makes it exceptional? How will a customer feel after buying it?

The power of a story is perhaps best demonstrated when people buy vintage items, whether they are fine art, antiques or an iconic guitar, such as the ones sold by my company, Reverb.com. Also relevant: the story of the people who owned or made the object -- something called the provenance. Not every item has a deep history. Indeed some objects are brand-new. But if an item comes with a story, this imparts a greater and deeper value.

3. Throw in a little something extra. Customers love it when a favorite company goes the extra mile to show its appreciation. Companies should always add a little extra flavor, whether a simple thank-you note or a small gift packed into a shipment, to give their customers something unexpected so they want to return again.

For example, I have seen sellers toss in small items -- free guitar picks, branded cables, logo stickers -- and customers eat them up. These extras can make buyers feel special.

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4. Know the community and get involved. To increase their popularity and recognizability, companies should tap into the online community surrounding an online marketplace and interact with buyers and other sellers as much as possible. Social media is a natural avenue for this sort of engagement, and some basic ideas include the following:

Tweet a “thank-you” to a customer.

Share the listings from other businesses on Twitter or Pinterest.

Engage with customers who post pictures of your products on Instagram or Pinterest.

Connect with influencers on Twitter by following, retweeting and sending direct messages.

Share buyers’ and sellers’ blog posts on Twitter and Facebook (but always include their social network handle so they will know).

Offer to write guest posts for community members who have blogs.

5. Clearly state the company's policies. Companies must have clearly defined policies and protocols in place to make their customers confident that their buying experience will be fun and painless.

When companies clearly outline policies for shipping and handling, returns and customer service, customers know that they are dealing with a serious business that is honest, diligent and trustworthy.

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