eBay is now a prime market place for selling just about anything online from antique buttons to sexy photographs of your girlfriend. And if theres a demand for your item then it will probably sell. You should then make a nice profit and be encouraged by your success.

But can you always make money on eBay? Is it as easy as were all led to believe?

Well, common sense tells us that it all depends on what youre selling, the competition and the market for your product.

After all, eBay is essentially an online market place that brings together international buyers and sellers to do business and the basic economic law of supply and demand applies.

So what basic factors should we consider before we start to sell on eBay? Can virtually anything sell and make us a handsome profit?

The answer must be a definite No - especially if the profit motive is important. And it must be, because we dont want to waste our time just breaking even or - dread the thought - making a loss.

But, for example, if youve really got your heart set on selling nineteenth century sweet wrappers on eBay because its youre passion in life - youve already been divorced twice because of your obsession - then you just need to stop and think for a minute.

And before you rush out and invest 500 in a gold plated, digital camera, hand crafted by Balinese maidens, just because you know it will produce the finest quality images of your antique wrappers, it might be wise to first consider the following essential factors.

is there likely to be a healthy demand for your product? Is it something people need or want to buy - hopefully on a regular, repeat basis?

is the potential market big enough so as to make a decent profit (say a minimum of 40% mark up on cost) and can that profit be sustainable?

are there others already selling the same item? If so can you compete on a price basis or offer something different to justify a higher price?

and finally

can you maintain a reliable supplier of your item so that you can consistently buy at the right price and sell at a profit?

So what Im saying really here is that before you dive into the eBay ocean make sure youve got your swimming costume on!

Or, to put it simply, before you decide what you want to do, or what niche you want to concentrate on, you need to be fully aware of whether its even possible to do it at a profit.

So the basic message is: Dont let your enthusiasm or obsession for a particular market blind you to the basic economics of what youre doing. After some careful consideration, you may have to totally rethink your plans and abandon your previous, cherished, pet ideas. If its not going to pay then you dont really want to do it.

But sometimes you will never know unless you try and you shouldnt be afraid of trying to sell something totally different. However, always make use of eBays feedback feature as a useful research tool. And what I mean by that is studying the feedback of existing sellers in your general and particular area of interest.

You can quickly discover what volume of sales they are achieving; what their average selling price is; which country they are operating from (this can be important for some products); how long they have been trading etc.

All this information can help you get an overall feel for that market and you can then test out your idea with some confidence based on facts rather than a personal, well intentioned gut feeling.

And if you find that someone else is already selling what you had in mind then this isnt necessarily bad news. Maybe you can offer the same product cheaper ( but try to avoid a price war if you can), or promote it in a different way or sell it with some other product as a free bonus. Try to think creatively and outside the box to make yourself different.

If you discover that youre the only seller dealing in a particular item then perhaps it just cant be done profitably. Maybe someone has already tried it and abandoned the venture as a waste of time. Or, conversely, you may have discovered a unique and hopefully profitable niche!

Another vital consideration is your view of just how much income you want to make from eBay trading.

Do you see it a just a part-time, weekend affair or as a full time career alternative? If youre aiming high then what you intend to sell is very important.

Would there be enough in the antique sweet wrapper market for you to reach, say, your 50,000 profit target? Probably not, you must be the judge, but you might easily achieve that figure dealing in more high ticket items.

So, in conclusion, you need to be absolutely sure of two things.

The first is to ask yourself if your market is financially viable. Are you going to make any money?

And, secondly, if you believe that money can be made then does the amount compare favourably with your income goals.

The answer to these essential factors should determine your activity. You may have to take some tough decisions but in the end you will benefit financially and develop a successful and fulfilling eBay business.