Engine in or out?
Engine in your about right, but you will have a few issues in the engine bay, door shuts and boot, but they may be able to get round the boot lid on the zed as its easily removeable. You can help by removing all the plastic interior, carpets, seats, rear lights etc as this will reduce on cost and mean not as much masking out is needed.. Take it all out and get a trailer to take it too the paint place..
With the bay, if you choose a "complimentary" colour then it wouldnt be a bad thing when you open the bonnet...
Engine out, more like 5k...
Also, you have resale to consider... Why has it been done etc etc...