Solution to provide phone calls for pfsense clients

  • hi all

    i provide internet for some residence compounds, any body can help me with solution to provide time limited phone calls for my pfsense clients, since our phone company charge me a flat rate for using their internet and have free cell and land lline phone calls, so my clients can benefit from this offer and the limit is to let all users have the chance to use this service and not the 1st holder of the line only.

    really appreciate the help