I think the minimum acceptable qualification to flaunt say on a business card would probably be PHD ( you can also call yourself Dr yay

). Too many people have Undergrad and Masters degrees these days so it isn't seen as such a big deal nowadays.
At one time not may people went to University, and if you weren't one of the Eton brigade and from an average background, then only people who had the ability to study a rigorous academic degree went. Now it seems every man and his dog goes to Uni, and the degree has been devalued. You see universities all over offering degrees in Film Studies and Cultural Studies which are unlikely to get you anywhere.
I'm Canadian, and in Canada the trend for large amounts of people going in to higher education started off much earlier then here in the UK. It has got to the point in Canada where a Masters degree is the minimum acceptable qualification for many jobs.
Not trying to offend anyone, and If I have then I apologise. Thought i'd give my 50 cents....