If a package is to arrive at my door before shabbat can I then take it in/open it on Shabbat (if the contents are not muktza) or are there further issues besides techum, e.g., Kinyanim or others.
"My door" is in a carmelis.
"My door" is in my reshus hayochid.
TO MAKE THE QUESTION EASIER TO ANSWER:
It is possible to open the package in a permitted way on Shabbos; the contents are needed for Shabbos.