So you can swap engines, would like to know what was involved, he says all electrics work.
http://www.ebay.co.uk/itm/range-rov...150231?hash=item1a22de6657:g:wtkAAOSwOtdYVmot

Air con would be the hardest bit to implement I would imagine, given that the engine is different (but by no means impossible!)
Heated seats are most likely the elements broken and easy to fix, and my guess on the central locking is a dud drivers door latch - if it works on the key, but not the remote, then usually a sign the motor is burnt out/seized solid
 

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