Its always hard if you just started to sell your items.
And its based on what profit margin you are going for and the product you are trying to sell.
You have to look at several things.
1. The Product your trying to sell ( sell whats in season)
2. Supply VS Demand (If supply is higher then demand you will loose money)
3. Price you pay to aquire product. (if your paying too much and generating too small a profit your paying too much.
4. How much to charge (lowest price usually wins a sale.)
5. When is relisting a bad thing ( how much profit you loose if you relist.)
Lets say your selling DVD's .. Literally thousands of sellers are selling dvd's Most people jump in thinking they will make thousands doing such. But that is not the case. You can make some money selling them but you have to be smart about it. Right now is not the best time of year for this item as demand slows because all the big summer movies are comming out and people are not cooped up in the house with nothing to do. So with 20,000 sellers trying to sell items like this they will have alot of trouble making the best profits unless they are volume sellers.
People think they can just buy a dvd lot off of ebay and resell it for extra money. Problem is that those lots sell each film for $3.45 and up for each movie plus its shipping. The average selling price is 99 Cents. Plus shipping based on the sellers shipping price.
Paying $3.45 for each movie eats up most of your profit potential.
Sellers like myself can buy 100 hit movies for $50.00 or $100.00
Using local advertising. Thats 50 cents to a dollar for each film.
Maximizing the full potential of each sale. So it doesnt hurt to relist the item several times if needed.
Paying $345.00 or more for 100 movies basically kills 85 percent of the profit potential of the item.
Buyer will look at a few things. Aside from the movie and the condition of the item.
1. Starting Bid
3. Seller Feedback
4. Sellers average sales per month.
And they will most likey choose a movie from a higher feedback. That is currently selling more then 100 items per month.
Key is to be patient. If you have a low feedback rating (aka under 200) then you have to slowly build up your feedback and then your level of trust with your buyers.
Just dont give up, It takes time. Took me over 2 years to make my first actuall profit on ebay.