Thanks for taking the time to share this resource Karen
I don't need to send a lot of faxes so have always used
FaxZero - it allows up to two free faxes per day, 3 pages each - the cover page carries a small ad (like a banner ad), but it's unobtrusive.
When I was first starting out as a virtual assistant I tried eFax (they had a free-up-to-a-certain-point plan at the time) and really liked it. I just didn't use the service enough to warrant paying for it, hence the switch to FaxZero.