No its not a fair system. The sceptic in me agrees with Bleve, but whichever way you approach the argument there are significant pitfalls.
An unregulated sector means you get cowboys, conversley a heavily regulated sector risks pricing or pushing decent assessors out of the market, particularly self employed ones.
So its a catch 22, the middle ground, some say, is self regulation, which does seem to work in part, however as Bleve points out there is always going to be a vested interest somewhere - groups of people or trade associations or organisations with vested interests on how the industry self regulates itself.
Also I would agree Meerkat that if we are going to question the competency of private
assessors we must also question the competency of enforcers too.