Here are some general price ranges:
M1871/84 Seitengewehr: This standard issue German bayonet can range from $150 to $500, with an average price of $250-$350.
M1898/05 Seitengewehr: This improved version of the M1871/84 can fetch slightly higher prices, ranging from $200 to $600 with an average of $300-$450.
S98/05 Seitengewehr: This versatile bayonet, compatible with both the Gew 98 and Kar 98k rifles, can be priced between $250 and $700, with an average of $450-$550.
S84/98 Seitengewehr: This scarce and highly sought-after bayonet can command even higher prices, ranging from $500 to $1000 or even more.
M1884 Jäger Cleaver Bayonet: This unique and rarely seen bayonet, originally designed for the Jäger corps, is the most valuable of all German World War I bayonets. It can fetch several thousand dollars or more, making it a highly prized collector's item.
Remember, these price ranges are just estimates and actual values can vary significantly based on the specific bayonet, its condition, provenance, and the market demand. It is always advisable to consult with experts and collectors to get a more accurate valuation.