Hi Faisal
To answer your question you should take every opportunity to get supporting documentation and letters.
The documentation you need should go beyond a simple diagnosis. You need to get people to document how your conditions affect you and what they prevent you from doing in your day to day life.
Have you read the PIP guide from this site
www.benefitsandwork.co.uk/guides-for-claimants/pip I think you will find it very useful.
It is important to note how points are accrued and make your claim with this in mind.
Please make sure you answer the questions based on your worst days.
I hope you are successful in your claim.
Regards
Pete
