Cost Basis

Cost basis is the total amount you paid to acquire a card, including the item price, shipping, any buyer fees, and grading cost if you graded it yourself. It is the figure your gain or loss is measured against: a card's unrealized gain is its current value minus its cost basis.

Recording cost basis accurately, ideally at the moment of purchase, is the foundation of treating a collection like a portfolio. Without it you cannot honestly say whether a card made or lost money, and collection-wide it reveals where your money is actually concentrated rather than where the value merely appears to be. For a card you graded yourself, the grading fee is part of the basis too, since it is money you spent to get the card into its current form.