You can put a total figure, but you have to have a corresponding list / worksheet that details each item and the cost basis totaling to any profit gained. When you enter the totals, you need to have documentation that explains what makes up that total and references which cost/valuation method you used. If you can, estimate when the purchase was made and for how much (to the best of your recollection) for each item. You can print out a sales log from Ebay that will be a great place to start, then for each item enter a cost and calculate the profit. Keep in mind that these were business transactions to a certain extent, even if you did not form a company, and that there are expenses that are deductible such as packaging costs, postage (if shipped for free), mileage to and from the post office, general office expenses, Ebay listing fees and final value fees, etc.
