1. Condition: The condition of the bill is crucial in determining its value. A well-preserved bill with minimal wear and tear will be more valuable than one that is heavily circulated or damaged.
2. Series and Signature: The series and signature of the bill can also affect its value. Certain series and signatures are considered more collectible and may command a higher price.
3. Rarity: The rarity of the bill plays a significant role in determining its value. Some National Currency bills from specific banks or Federal Reserve districts may be scarcer than others, making them more valuable to collectors.
4. Seal and Printing Quality: The presence of the brown seal from Kansas City, Missouri, can add value to the bill. Additionally, the overall printing quality and design elements of the bill can contribute to its desirability.
5. Market Demand: The demand for 1929 $20 National Currency bills among collectors and enthusiasts can influence their value. If there is a high demand for these bills, their prices may rise.
It is important to note that the value of banknotes can fluctuate over time, and it's advisable to consult with reputable numismatic experts or refer to specialized price guides to obtain an accurate estimate of the bill's worth.