Using email-to-fax services of RC, if you want to send a custom cover page instead of using the RC cover pages, the only method of safely ensuring your custom cover page gets sent as the first page instead of the last page is to merge your attachments and your cover page into a single file (Word, Excel, PDF). 

We experimented with this a lot and found that even though we could always attach a cover page as a separate attachment file, it would never reliably get sent as the first page.  

Our solution was to setup an email processor, where we have all our users email their faxes with cover pages to an internal email account (eg.  fax-number@our-domain.com).  We have setup a program on our server that picks up all these emails and merges the attachments into a single PDF file with any attachment that contain the word "cover" gets merged as the first pages.  Then the program forwards the PDF to the fax-number@rcfax.com.

We have recommended to RC several times in the past to enable a similar solution, but have received zero indication that they would try to implement this.

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