Fax gateway solution with Digium hardware

We would like to provide fax service to our customer with Digium PRI card, is it possible to achieve the following IVR/Fax scenario:

  1. The customer rings a 1300 number and answer by the IVR
  2. Customer authenticate with mysql DB by key in account number as DTMF digits
  3. Upon successfuly login, IVR provide main menu with 2 options:
    1 for voice mail (allow user to leave a message)
    2 for receive inbound fax (the idea is to receive the fax and converted in tiff file).

Please note: for option 2, the IVR will play a beep sound to signal the caller to press a start/send button in their fax machine to send the pages across.

Questions:

Can you place IVR in front of the fax? The idea is to keep the Call ID consistent. If not, what is an alternative solution?

Is it possible to receive multiple fax pages?

I am aware that Digium card has on-board echo cancellation, to use for voice and fax, this feature has to be turned off, does the voice quality be affected by turning off echo cancellation?

what speed / resolution does it support?