I got mine done by a clinical psychology master’s student supervised by their professor. It was half the price (and my insurance ended up covering 40%), no GP referral required. If anyone reading this has a college or university near them, check if they have that option. Added bonus is that the students are usually more up to date on current diagnostic criteria compared to someone who has been practicing in the field for a while.

I also get my dental check ups done at the university dental school for the same reason.