The general perception is that consumer-to-consumer online trading platforms are mostly for tangible products. However, there are more ways to earn additional or even primary income online. We examine six case studies that demonstrate how a writer, an entrepreneur, a guest house owner, a masseuse, a restaurant owner and an artist can earn income by selling on an online marketplace.

Case study one: The writer

Information is the most valuable commodity on the internet. It is also the easiest and most cost effective to distribute. Even if you are not a writer, there is plenty of information available on the internet that you can either purchase with resale rights or compile from various sources and then sell on yourself.

Information can be distributed in several formats. It can be contained in electronic format as ebooks (a highly cost effective mode). It can be burnt on a CD or DVD disc. It can also appear in hard copy as a professionally bound document. Books can take the form of anything from your favourite set of recipes to a 'how to' guide.

Case study two: The guest house owner

If you own a guest house, a lodge or a hotel, you will know that cash in the bank is better than empty beds. It follows that if you sell about half of the beds on an online marketplace at a reduced rate, you will sill make more than if those beds remained unoccupied.

Besides, by offering your product at lower prices initially, you will introduce new customers to your establishment. If they are happy with the accommodation and the service, you will get repeat business at normal rates and increased business from word-of-mouth referrals. You will also find that, as you build up positive feedback on the online marketplace of your choice, you will be able to demand higher prices.

The beauty of using the internet in this case is that you can respond quickly to low occupancy rates by listing your offer at the last minute.

Case study three: The entrepreneur

This is the classic seller on an online marketplace. It is a well-known fact that the best business involves buying something for a dollar and selling it for two. However, setting the prices at an unrealistically high lever can work against you, because people expect to find bargains on online marketplaces. If you do not provide your goods at a price that it is significantly lower than elsewhere, it is unlikely that you are going to sell much.

The idea here is for you to be able to offer your goods at a bargain and still make a fair profit. The key is to know what products to buy and at what price. You will also need to find reliable places from which to source your products. These could include real-world auctions, imports, wholesalers, liquidation sales, classifieds, garage sales and flea markets. The idea is to buy at the lowest prices possible, which often entails buying in bulk.

Case study four: The masseuse or reflexologist

If you can provide a service - almost a n y service - you could cash in on these skills using an online marketplace.

It may be worth your while to list your services on an online auction with a minimum starting bid and without a reserve price. You could consider offering this as a special offer to first-time customers only, as you do not want to alienate your existing client base. In the beginning, the winning bids may be low, but you will probably attract new, repeat customers who will be paying your normal rates for months to come. In time, you will probably find that the prices you can charge on the online marketplace will come very close to your normal rates.

This same principle can apply to any professional services. Consider legal services, web design, hairdressing, palm reading and many more. The ideal service to offer online is the one that entails little or no cost - so that almost all of the money you receive goes directly into your own pocket.

Case study five: The restaurant owner

Almost everyone goes to restaurants. Most of us end up going to a few of our favourite ones repeatedly. Here are some ideas for you, as a restaurant owner, to use to ensure that your restaurant is one of those favourites.

1) Auction on an online marketplace a three-course meal for two (drinks excluded), with the bidding starting from the lowest opening bid.

2) Auction a voucher for your restaurant that gives the bearer a discount when dining with four or more people.

3) Auction any special (a two-course meal for four, a speciality buffet, a Valentine's Day meal at the restaurant's best table, etc.) that will draw customers to your restaurant and entice them to return with repeat business.

Case study six: The artist

The more that you, as an artist, can get your work out there, the more the word of your good work will spread, resulting in referred sales.

Would you rather keep your work stacked in your studio or get it out into the world by auctioning them online? Even if you run at a loss initially, if your work is good, you will be sure to benefit from repeat customers, referred sales and positive feedback ratings that will push up the bidding on your subsequent auctions.

If you recognised yourself in any of the six case studies presented here, you may be inspired to start using an online consumer-to-consumer marketplace as a source of income.