text: what kind of taxes do i have to pay if i sell things on the internet? let's say that i decide to sell a few possessions (books, collectibles, etc.) online.  what kind of taxes would i be responsible to pay in that situation? depends.  if they are personal property, and you didn't sell them for more than you paid, it's handled like a garage sale, no fed taxes.  can't speak for the state.  however, if you start doing this as a source of income, the answer changes.