Because you acquired the home by a gift, your basis usually is the basis that your parents had in the home (what they paid for it, plus capital improvements they made over the years). It may be difficult to reconstruct this information, but their initial cost may be available (e.g., published on Zillow).
Items, such as interest, state and local income and sales taxes, charitable contributions, and medical deductions, claimed on Schedule A of Form 1040. Itemized deductions are subtracted from adjusted gross income to arrive at taxable income. The amount of itemized deductions is also subject to a reduction when adjusted gross income exceeds certain limits.