It's the entire amount. Given that the sale of banners and titles has slowed somewhat, we wanted to get the maximum benefit from something people aren't buying as much as when the titles and banners were released. This is also only one step in providing the City Treasury with additional funds, and you can expect to see additional methods in a future publish.
As far as lockdowns, what is it you are wanting to be able to lock down and why? We've had a lot of success so far with Governor interacting with the Crown and requesting special areas to be built to add to our library of town addons. Some of the add-ons include a market in the City of Trinsic, an Archery Tournament area in the City of Skara Brae, and a Peace Summit held in the City of Nujlem.