here's a guide Goodwill provides
https://goodwillnne.org/donate/donation-value-guide/
you should make a detailed list of what you're donating and make sure you get an acknowledgment.
should the value exceed $5,000 you need an appraisal.
Generally, if the claimed deduction for an item or group of similar items of donated property is
more than $5,000, you must get a qualified appraisal signed and dated by a qualified appraiser. a copy of the appraisal goes with your return.
