If you just need information to complete 1099....EBAY has FREE "easy to read" 1-page report that shows YTD totals for (order/gross sales, refunds, EBAY fees, shipping expense). Go to Payments, Reports, REPORTS (NEW) and select LAST YEAR.
GROSS SALES (from EBAY report)
-Refunds (from EBAY report)
-EBAY fees (from EBAY report)
-Shipping expense (from EBAY report)
-Other expense (cost of goods + misc. expenses) YOU NEED TO KEEP RECORDS
NET TAXABLE INCOME
You should create 2 spreadsheet (one for inventory + one for misc. expenses). Anything used for your business is deduction (cost of goods sold, packing materials, office supplies, mileage, etc).
You must file taxes as a "business" if you want to deduct expenses.