renaut grande espace - renaut espace electrical nightmare - sam1

Took car to local reputable garage (not renaut) as having problem getting into gear. Problem was master cylinder leaking whcih they fixed. They then said once fixed car wouldn't start. changed the battery still didn;t work. Got autoelectricain in who said may be started motor - replaced. Next it was ECU(?) and this was replaced (well over £1000). IN the middle of all this when we were getting upset they admitted that they drained the battery when trying to bring the car into the garage as I left it parked outside when I dropped it. they couldn't get it to move and ended up draining battery (I assuem) na dhad to push it into garage.Then it wouldnt start. Once ECU replaced car would start but electric throughout car had gone - automatic handbreak, dashboard, AC etc. car was moved to renaut garage and has been away from us for about 8 weeks in total. We feel that this was probably caused by them although they say these things happen in such cars. Is this true? If we had taken the car to renaut dealership in 1st place I woudl expect that this wouldnot have happened. They have agreed to negotiate on bill but are not taking any responsibility at moment. Any advice please??

renaut grande espace - renaut espace electrical nightmare - injection doc
batteries can suddenly fail without warning, especially once they get drained, but for all the other problems it sounds very much like they have iether used a mains booster ( rather than a ni-cad power pack) with the ign on and spiked the sytem or jump leads and may even of connected wrong way round to damage so many components.
Seen it done to an Omega CDX which blew every electronic component in the car ! including sat nav,abs,auto box ecu eng ecu light curcuit,ac system etc.
I feel that this is fairly serious and you will need to keep the old electrical components and have one or two inspected for a possible cause and seek proffesional advice from a vehicle inspector to pursue if needs be.