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).
Certain employees, such as full-time life insurance salespersons, who may report income and deductions on Schedule C, rather than on Schedule A as miscellaneous itemized deductions.