1. 1776-1976 Bicentennial Half Dollar (Common Date):
- Circulated: $1 - $2
- Uncirculated: $5 - $10
2. 1976-S Proof Bicentennial Half Dollar:
- Proof: $10 - $20
3. 1976-D Bicentennial Half Dollar with Doubled Die Reverse (DDR):
- Circulated: $50 - $100
- Uncirculated: $100 - $200
4. 1976-D Bicentennial Half Dollar with Close AM:
- Circulated: $5 - $10
- Uncirculated: $10 - $20
The values mentioned above are approximate and can vary based on market conditions, coin grading, and specific characteristics of the coin. It is always recommended to consult with experts or reputable coin dealers for the most accurate appraisal of a Bicentennial half dollar.