The cost of a genuine katana can vary significantly based on several factors, including the sword's quality, craftsmanship, materials used, age, historical significance, and the reputation of the swordsmith or manufacturer. The price range can be quite broad, spanning from a few hundred dollars to several thousand or even tens of thousands of dollars.

Here are some approximate price ranges to give you a general idea:

1. Mass-Produced or Entry-Level: These are typically modern, factory-made katanas produced in larger quantities. They often use standardized materials and production methods. Prices can range from around $100 to $500.
2. Handmade Replicas: These are katanas made by skilled craftsmen who aim to replicate the design and characteristics of historical swords. Prices for handmade replicas can start around $500 and go up to a few thousand dollars.
3. Custom or Semi-Custom Katanas: These are individually crafted swords, often made by skilled swordsmiths or artisans who specialize in creating high-quality blades. Prices for custom or semi-custom katanas can range from a few thousand dollars to several thousand dollars, depending on the level of customization and the reputation of the maker.
4. Antique or Historical Katanas: Genuine antique katanas that are several decades or centuries old and have historical significance can be quite expensive and highly sought after by collectors. The prices for these swords can vary widely, depending on factors such as age, condition, provenance, and the reputation of the swordsmith. Antique katanas can range from tens of thousands to hundreds of thousands of dollars or more.

It's important to be cautious when purchasing a katana and to ensure that you are dealing with a reputable source or knowledgeable seller. Authenticity, quality, and craftsmanship are crucial considerations when investing in a genuine katana.