Hi Milikilawat
There is a Guide to PIP Claims and Reviews which is 139 pages. The review advice starts at page 130 - but if you are unfamiliar with the PIP questions then you would be wise to go back to the beginning of this guide as after the introductory information - which is key to understanding terms such as 'reliability' it gives advice and sample answers on how to answer every question.
benefitsandwork.co.uk/guides-for-claimants/pip There are supplementary guides for certain conditions - if one is applicable to your friend.
benefitsandwork.co.uk/guides-for-claimants/pip The PIP training is a separate charge. It is excellent training - but many of our members successfully fill out their forms using the Guides only - so you do not have to purchase it unless you want to.
BIS