My 2004 Pac won't start
 

Hello to all! I am new, this is my first post. so I apologize if my problem have already beed discuss. I am sorry this is so long.

I have a 2004 pac. Last wednesday. I strated it in the morining it started fine like it has always. then all of a sudden it started losing power and eventually shut off. I tried jump starting it but was not successful. So I took the battery to the local auto parts store. They tested it and and said it was bad. I bought a brand new battery right there. Took it home and installed it in the car. all the lights came on and seem that the batterty was good. Then I tried to start the car but nothing, just won't start. won't crank, won't turn over, just as is completely dead. so I took it to my local mechanic. He later told me it was the starter. he order a new starter and installed it and still the same situation. won't start. instead I get this
error message that the car needs to me in park before it will start. I know it is in park. I moved the gear back and forth and set it in Park but still get the message "not in Park". Has anyone had this problem. I am planning on taking it to the dealership, any idea how much money it will Cost??