Last Chance

Before it finally goes into expensive repair shop - does anybody out there have any experience of power on to camera. Not sure whether or not it's the switch or something else like a chip (the micro electronics kind) I have tried lubrication (spray) it seemed to switch on for a while but since has been intermittent and now stubbornly refuses to turn on. It is definitely not the batteries themselves. I have also had a fiddle with the battery contacts. I have tried online support but a lot is about resetting and doing things that require it to be turned on. So before I go and spend all my Christmas money on camera repairs - Any thoughts?

ps The last camera I sent in to be repaired - I never saw again