George said he paid £3,000 to access private assessments for ADHD and autism due to NHS waiting lists.
"That's a painful amount of money to spend, but I am fortunate that I can afford that," he said.
In England, 236,225 people were waiting for an autism assessment as of June 2025, according to the National Autistic Society, while some adults face an eight-year wait to access NHS ADHD services.
In Wales, there were 16,812 children and young people in Wales waiting for an ADHD or autism neurodevelopment assessment as of 2023, according to Senedd research.
"There are so many barriers to access, and the waiting lists are unacceptable," said George.
"The question is, are we going to accept that, and what are we going to do to change it?"
The National Autistic Society says some people opt to pay privately for diagnoses due to shorter waiting times, but the charity says some experience difficulties having their non-NHS diagnosis accepted by local authorities and NHS health services. It advises people to check whether a non-NHS diagnosis will be accepted in their local area before going ahead with a private assessment.
Similar concerns have also been raised about private ADHD diagnoses, with the charity ADHD Aware saying that, while some GPs will recognise a private diagnosis, others will not.