why not leave them installed and just don't give your users access to the menus etc

Hello,

You can either add a group called 'No one' to the Accounting menus, or Your user should not be a part of any of the accounting groups.

To answer: "When I try to add a customer it says "The following fields are invalid: Account Receivable, Account Payable" "

These are property fields, which you can make non-mandatory by a simple inherit.

Hope this helps. Thanks, Serpent Consulting Services.