1. Does she need to carry 21000 CAD(must for family of 4 person as pof) to show off at immigration even if traveling alone? - Yes she does
2. Does her presence in Canada is must to receive PR card or PR card will be deliver at address given to immigration counter? -Will be delivered to the address, sometimes there are photo specs. issues, and the photos needs to be sent again, if for some reason she does not get the PR cards she will need to get a Traveling document to enter Canada again
3. Does it affect anything if my friend and his children will travel later? - they will have to travel before the visas expire, otherwise no issues
4. what should be reply of his wife in response to immigration officer if he ask about non accompany family members? - she can tell the truth and that they will land on a later date (but before expiration of visas of course)about no.2 - if someone makes a first landing in Canada, applies for PR card and exits without getting it. There arises some photo issue or somehow he can't receive the PR and it gets lost, he will be requiring a travel document to re-enter Canada. Did I understand it correctly!
Now what kind of travel document it would be and from where can one obtain it,...is it from nearby Canadian embassy ! Just wondering why he can't re-enter on the visa he already has on the PP, is that visa valid for one time entry only !!