If the fair market value of a single item or of a group of similar items you donate exceeds 5,000 dollars, you generally must obtain a qualified appraisal. In that case you complete Section B of Form 8283 instead of only Section A. Similar items such as multiple pieces of furniture or several works of similar artwork are combined to see if the 5,000 dollar threshold is met. A qualified appraiser prepares a written appraisal report and signs the declaration on Form 8283, and an authorized representative of the charity signs the donee acknowledgment. For some very large deductions over 500,000 dollars the appraisal report itself must be attached to your tax return. Failure to meet these appraisal and reporting rules can cause the IRS to deny or sharply reduce your deduction.