I get 5000 to 7000 pages of fax a month. Think one line will do it?
200 pages a day? WOW.
Given that most of the faxes are coming during business hours, I would think you might need multiple lines.
One option would be to reserve a second line for small faxes and complete medical records or the like are directed to fax board.
We use Brother MFC fax printers, but do 10-20 pages a day. Might work for the low volume stuff but not sure about that high volume.