1)Yes, probably.
2)Yes, probably.
3)Yes, probably.
1)Most sellers use Canada Post/USPS for shipping. Some use UPS or other couriers. Those get expensive- there is a very long thread about this on the Buying Board.
If the parcel is an import, you may be required to pay a $9 Canada Post service charge, GST, and applicable duty.
2) If the parcel will not fit in your box, or if fees are to be charged. , the postie will knock
3) If you are not home, the postie will leave a note and you can pick up at your local PO.