I am currently developing an auction desktop application. At the moment I am storing the buyer and vendor information in 2 separate tables within a MySQL Database. Currently the data for these tables is unencrypted (whilst in development) but I am planning on using PBKDF2 to encrypt these with a salt that will be stored within a .properties file. The MySQL server for this application is stored on the local drive with the application. And no network traffic is needed for this program to work, nor has any been planned for it. There is a high probability that the client will connect the computer hosting this application to the internet through the local LAN/WLAN.
Anyway, to my question. The client has just informed me that they also need to store the bank details of the vendors. So if I made another table, where the data is linked through a foreign key to the ID of the vendors, and this table contained all of the bank details, and then hashed this information with a salt that I could store in a .properties file, which is then hashed as well, would this be a secure enough approach? Or would there be a better way to approach this problem (besides steering clear of storing bank details)?