OK I have finished the CAD...again.
I've cut a few things and applied cheaper solutions to more expensive items; hopefully this will make it cheaper without changing its nature too much, it's all down to the quotes I get back in the end.
Revised the way to connect aluminium and plastic
Changed the standoffs for more affordable ones...not a fan but hey...
Removed clamp for power switch
Replaced power switch with a cheaper reset switch ( it does the same thing) but it costs £3
Removed the sleeve/braiding from the power switch
Removed the sleeving/braiding from the keyboard
Reduced the amount of punching required in the aluminium
I'll email the CAD files and wait for a quote.
Thanks! 
Is this to reduce your cost, or is it to reduce retail price? Because I thought the price was arbitrarily chosen:
Everyone who registered has come up with suggestions about price, ranging from £70 to £520 so we're going somewhere in the middle to make everyone happy