Hi Toni, its been a long time!
I have an agent that I have done some work for that is part of about 4 or 5 associations to do with Real Estate and professionals - he posts them on every website of his, on all his signatures, in his emails, where ever he can put them beside his company name - he will do it!
One it is a sign to the public that you abide by a set of rules, you work to certain guidelines and I suppose it makes people feel at ease working or buying through you.
Also with all the bad press about dodgy agents in Spain, it give the potential buyer that piece of mind that you are part of a professional association and you are not just selling homes from your home or a car!
Remember buying a home is one of the biggest decisions that you will ever make in your life and obviously you want the assurances that you are dealing with the right people, so maybe this helps?
I personally do not know IF these associations do check ups on companies, if they monitor their members in anyway - I don't know?
To me they are a sign of professionalism, trust and they make you feel as though it is a company that you can deal with, however - you could make up any kind of association yourself for your websites and who would know?
Good discussion topic this one...