According to USACoinBook, an 1803 Draped Bust Quarter in average condition is worth around $850,
while an uncirculated coin can be worth as much as $23,428. If the coin is a rare variety, such as the "Heresy Quarter" with the word "LIBERTY" misspelled as "LIRERTY", it can be worth even more.
The 1803 quarter is considered to be a key date in United States numismatics, and is one of the most sought-after coins by collectors.