How to place front door

I have a 2002 buick rendevious that i need to get the front inside shell of the door off to look at the power window motor.

My back door only has a passage knob that locks but can easily be jimmed open. I am concerned with my security. Is this something I can demand to my landlord or do myself?

I brought a dsoor. At SutherLAnds. They told me the door was damage. I told them i needed antoher door. They did not give me anything. The Store manager was white!

Need some clarity on soliciting door-hangers in residential neighborhoods. Some mailboxes have a slot for mail and a slot for the newspaper. Can I get by with placing door hanger in slot were newspaper goes or...