I don't know anything about this machine personally, but am trying my best to understand LOL!
The system has been greatly expanded beyond the standard specification.
Inside the cabinet, the following have been added
16SLI 16 circuit Analogue Extension Interface - MRP £522 each
16DLI (x5) 16 digital stations - MRP £581 each
8TRK 8 port analogue trunk module - MRP £405
MCP2 main control processor - MRP £816
PSU B (x2) power supply expansion module - couldn't find price
TEPRI (x2) primary rate interface card - MRP £622 each
Only selling so cheap as we are aware that this is a specialist item (and it is sitting in my living room - it doesn't match my decor LOL!)
Also has potential to make profit on if you sell the pieces separately.
All I know that is not 100% on it this system is that the cabinet cover is missing. This cover was purely for cosmetic purposes and the fact that it is missing does not affect the system working.
I can deliver within a reasonable distance of North/East London or you are welcome to arrange a courier service (item is very, very heavy)
Cash on collection/delivery - or bank transfer if you prefer