Recently had battery replaced at a parts shop. He used a "Memory saver" plugged in under dash but now no radio, interior lights, door locks, or key fob remote functions.

Parts place will offer no help for what is obviously their foul-up.

Only local dealer is a known scammer & rip off place...

Can I do this myself (very limited auto knowledge) or does it have to go to a dealership?

Thanks for your help!