Avaya---out of production.
Panasonic does all except use hookflash.
No, the customer is not allways right.
If I were going to do this locally you would have to pay up front and sign off on how the system works and agree to accecpt it as is. Any change would be T&M.
Whenever weird parameters are set, it's been my experience that when the end product is seen and used, changes are required that are far outside of what was specified, and payment is withheld.
Been there, done that, will leave it to someone who has not. An effort was made to answer your question, which several people did. My input was
an exact match except for the hookflash, and was comprised of a low cost system that is not out of production, has the best wireless, voice mail, caller ID routingetc,etc. You can't beat a Panasonic in a house,
it's too flexible. Your not wrong for wanting your system, It's just a thing I steer clear of.
I don't think you will find a lot of successful
phone companies ready to run over and install the system you spec. or sell it, unless they get money up front, like on the Internet. Then when it has problems you get to play the Internet Game--- Heres Bob!!!!!
