A new Centovacast module is available, but it's an early alpha.
To install, download the attached centovacast.zip and unzip the file. Upload the centovacast directory to ~/components/modules/ and go to Settings > Company > Modules to install it.
centovacast.zip
Please give it a spin and give us your feedback. Here's a sample welcome email you can use for your Package:
So it creates a new invoice just for the late fee? Is that the most common way, or do some places add it to the existing invoice? I know in some places you can't edit the invoice once it's been created, but I don't know if they have exceptions for late fees. Just curious, in case we add to the core in the future.