if you enlarge the last photo taken of the victim Halbach standing next to the Rav 4 (believe it was taken the morning of her disappearance) you can see that her keychain had multiple keys on it. Yet the key found in Avery trailer next to the nightstand only had one key (Rav 4) on it. Not sure about you but i dont change my keychains on a daily basis.
If Steven Avery is really guilty hes the dumbest criminal in the history of criminals. Sitting on a 36 million dollar lottery ticket, and kills a woman and burns her body 10 yards from his house and hides her car with some branches on his property.
If he get exonerated, hes got the worst luck of anyone. Spending most of his life in prison for crimes he was falsely accused of.