If you are trying to meet QM standards and Appendix Q, you are correct in needing all documentation.
If you are trying to meet the basic 8 factor test for Ability to Repay, not rising to the level of a QM, then you may be able to forgo some documetnation based on other verified information. You do not have to meet Appendix Q to satisfy only the ATR test.
_________________________
Old School Banker