Take a look around the APBC site, this page shows some articles by full members:
Articles by APBC Full Members | Association of Pet Behaviour Counsellors
I would rather go to APBC or COAPE than APDT qualified people, the APBC and COAPE people are usually far more qualified and use kinder more up to date methods.
If they are full members of the APBC they will have to pay for that (all the education that involves), plus they will be fully insured and above board.
This is what they say about their full members (there are other levels of membership below this):
"FULL MEMBERSHIP
Full members are practising behaviour counsellors who have achieved at least a higher degree level education in companion animal behaviour and related subjects, obtained relevant practical experience, and who have been in practice for a minimum of one year. In order to gain full membership the individual will have had four referenced case studies scrutinized by the application selection committee (which is comprised of eight full members of the APBC). Full membership can also be gained by achieving ASAB certification. Many pet insurance companies cover, at least in part, fees charged by full members."
So they are pretty highly qualified and have practical experience as well.
The report and consultation may also include back up for a period afterwards.
Sue