This may sound like a cracked record, but for a key policy, we've had astonishingly little detail. The mansion tax has been laid out by Labour as this unicorn mythical panacea. More Scottish nurses? Mansion tax. More money sloshing round the economy? Mansion tax. How do we keep taxes x, y and z down? Mansion tax.
But the truth is, although figures of how much it could raise have been bandied around, no one is yet clear how that breaks down. And although the numbers of people actually paying it will be minuscule, there may be many floating voters in tightly fought marginals like Hampstead and Kilburn, Westminster North, Hammersmith, Battersea who simply have no idea of the figures involved.
When I asked for clear figures , Ed Balls' office told me that properties between 2-3 million pounds would pay 250 pounds a month. And what happens to properties North of that?
We simply have no idea. Ed Balls' office simply said "we've set out far more detail than most oppositions. Treasury and HMRC have modeled it but they've refused to share it with us".
Now, don't get me wrong. I know for the vast majority of the UK this sort of question is Angels on pin heads. Who cares, you might think, what the really wealthy have to pay. The answer is simply: they do. And they're voters. And many of them in the South East will be living in these key election battlegrounds that may decide the eventual seat numbers.
Any wonder we know so little?