I would be a bit dubious about paying an individual who is not part of an organisation like CitA or AgeUK or a specific charity, but I don’t think in itself it is unethical. As others have said, is it any different from paying for other services?
I might be concerned that the person would distort what a claimant was saying, or be dishonest in order to get paid for a successful claim, but they are not automatically going to be dishonest. It is obviously safer if the person helping with the forms is backed by an organisation.
Qualifications? (Not all gardeners or cleaners have a qualification.) Experience is more important.
As a volunteer I have completed many PIP and AA forms, and helped clients to challenge a decision or appeal to Tribunal. As far as I know, all those I helped were successful, but we didn’t always get feedback.
I had training and developed expertise in this area, ( not a ‘qualification’, as such, though I do have a French degree!) but that still doesn’t guarantee success.
I have read decision letters from DWP which totally ignore or distort what claimants have said. They even contradict evidence from medical specialists. The system is flawed. There is no guarantee that a completed form will lead to a successful claim. In any case, it is followed up by an assessment, though nowadays very few are done face to face. I have no proof, but I believe assessors have targets and are expected to fail a certain number of claimants each day.
In theory there is nothing to stop me (or anyone else) accepting payment for helping a person to complete a form. Most people I helped were very grateful. In 15 years as a volunteer I only met one person who I believed was not a genuine claimant, ie was lying.
I met one other who was genuine but I had to tell her that after careful consideration I did not think she was eligible and if she went ahead she was unlikely to succeed. She trusted me and did not continue. In fact she had done no homework( not unusual) - she had not studied the criteria.
Most clients turned up for an appointment not even having read the form. They had not even managed to fill in their name and address. Some could not correctly provide contact details of their GP or medical centre. Some couldn’t read, or were too panicky or anxious to focus. Others totally misunderstood questions and told me what they could do, and needed to be encouraged to tell me about what they struggled with or could only do with help or support.
My Mum eventually claimed AA but only with help to acknowledge where she struggled. She was such a positive person who found ways to solve her problems, not dwell on her restrictions.
I guess if I needed the money I could offer my services for a ( reasonable- not £150! ) fee. It would not be unethical. Some claimants can afford to pay. It is not always easy to access free help. But like many other situations, it is open to abuse.