Geezer, I live in Oz. and was n`t quite sure. some said that they had to have an address in their electorate, some said they had to live there for a certain number of days every year . There is a ground swell of opinion here that they should be required to be permanent residents in their constituency The pollies are not to keen on it though.
In the constituency that I live in, we had six candidates, three of them lived within the local constituency, two lived in a neighbouring constituency, and the remaining one (who won the seat and I personally didn't vote for him), lived in London, which was about 125 miles from my constituency. So in other words, no they don't have to be, but it can be useful if they know the area that they are about to represent!