what documents can one prepare pre-ITA ?
There are many. All documents need to be scanned so that they can be uploaded. They also need to be in English. If you have any doc in another language, you will need to get a certified translation. Below i've mentiined a few things that you will definitely need. Final list should be provided to you by CIC when you fill out the post ITA forms.
1.Birth certificates of entire family
2.Passport copies of entire family
3.Marriage certificate
4.Education proof including ECA ( husband & wife if claiming points for both )
5.Previous Employment docs
6.Digital photos for entire family
7.Ielts results
8.Tax return details (if applicable)
9.Police certificate of all countries where you have lived > 6 months even if its in parts