I've been using CallWave. It costs approximately $48 per year. That's only $4 per month. The reason I chose CallWave was because of the Notary Signing Agent business. This way the title company could fax me any last minute changes. Finally, I have a standalone fax machine which I use to fax documents out.
With CallWave you are able to have a phone number and a fax number. The phone number can ring at my cell or home number. Additionally, I use this number to give to clients, and other business contacts. This way I don't have to have a 2nd phone line in my house. When I was searching for free fax, I could only receive may be 10 pages. This wasn't good for the business.
I hope this helps.