Here are a few considerations that can affect the value of the autograph:
Authenticity: The most important factor in determining the value of any autograph is its authenticity. Ensure the autograph is genuine and not a reproduction or copy. Look for signs of authenticity, such as consistency with known examples of Jim Davis's signature and any accompanying documentation or certificates of authenticity.
Condition: The condition of the napkin and drawing can also impact the value. Factors such as stains, tears, or fading can diminish the value of the autograph. A napkin in good condition with a clear and well-preserved drawing will be more valuable.
Drawing: The nature and complexity of the drawing can also play a role in the value. A simple sketch may have less value than a more detailed or elaborate drawing. The subject matter of the drawing can also be a factor, with more popular or iconic images potentially adding value.
Provenance: If there is any information or documentation about the provenance (history of ownership) of the autograph, this can add to its value. Knowing the provenance can help establish the authenticity and provide a better understanding of the item's history.
It's worth noting that the value of autographs can fluctuate over time, and the market for collectibles is influenced by various factors, including trends, demand, and the reputation of the individual whose autograph is being sought.
To obtain a reliable valuation, it's advisable to consult with experts in the field of autograph collecting or memorabilia appraisal. They can assess the various factors mentioned above and provide a more accurate estimate of the autograph's value.