This is from IRS. Seems clear if you claim over $5000 you must have appraisal.

You must fill out one or more Forms 8283, Noncash Charitable Contributions and attach them to your return, if your deduction for each noncash contribution is more than $500. If you claim a deduction of more than $500, but not more than $5,000 per item (or a group of similar items), you must fill out Form 8283, Section A. If you claim a deduction of more than $5,000 per item (or a group of similar items), you must obtain a qualified appraisal of the item or group of items and fill out Form 8283, Section B. If you claim a deduction of more than $500,000 for a contribution of noncash property, you must fill out Form 8283, Section B, and also attach the qualified appraisal to your return.