engine will not start, no click, no nothing

I just bought this car and have had a bunch of weird problems with and supposedly no Chrysler Service person has ever heard of such a thing but of course I can bring it in and they will try to diagnose it (=$$$$$)! It was dead before so I jumped it and brought it to Advanced Auto Parts and they said I needed a new battery ($210 later) car started fine for a week, then engine light came on, again took it to AAP and they said the code was P0456 which 80% of the time was a loose gas cap, tightened it, and they said the light should go away in a couple of days. Then 3 days later I believed that I unlocked my ca,r and the trunk popped open as well, I went to start it, nothing, no click, no lights, nothing...tried 3 times, nothing. Thought it could be the key so locked everything up, shut trunk, went inside to get other key (FOBs). Tried that one nothing, couldn't get in car, pulled out both metal keys and tried them, nothing again...so I am locked out of my own car, no key to get into trunk to try to jump start it either. Dealership says if I can get in without having a new key made (very expensive$$$$) then maybe I can get the hood open to jump that way. But never heard of such a thing, no one seems to have ever heard about this, being totally locked out of my car and won't start even if I could get in?????