If your paying for an outgoing calling you should be able to FAX to the Number your calling
Laura Cohen commented
As a small business I am seeking the ability to send a fax to a phone number that is secure and HIPAA compliant. I subscribe to Office 365 Premium and do not want to pay a monthly subscription as this is an infreqent need. I prefer a model like the Skype Personal where you can purchase a card and use it to send faxes as needed.