It is helpful to post scans. If you, solely, are talking about US stamps I think you often should have an accurate perforation gauge, and a scan of the back as well. Outside the USA, watermarks may be essential for identification.
From earlier threads about people finding their stamps listed as rare and valuable, most of such rare stamps are a variety often not visible at first sight unless you are familiar with the variety, or they are listed on Etsy or
ebay as rare and valuable but cost more to scan than they are worth.