I am planning to sell a lot of parts that came of my motorcycle build. I am going to keep track of every item I sell, some are easy to determine if it is a loss or profit like parts that I actually bought then never used. But how do I go about parts that I am replacing/upgrading? For example I have a headlight assembly that came of the bike and was replaced with something else. Do I compare it to the price of the bike when it was bought or the total worth of the bike after rebuild or to the aftermarket part? In my view it is just a reimbursement of the whole project that covers a fraction of it, what would IRS think?
