Add the option to add a default attachment to all invoices/quotes

We have an A4 page worth of terms and conditions that we need to include with all invoices and quotes. This means we have to attach them with the email or ask the customer to request them, both options are time consuming. Could there be the option to be able to attach a document (such as a PDF) as a default? This would allow for extra information to be shared with customers as a matter of routine. Some other users might have detailed instructions for their products or returns options etc. that need to be included with every invoice and would save a lot of man hours! Thanks