this sounds bogus to me, because its selling off land that it claims the government owns. how did the government get it and why are they selling it? are they selling it or just letting you build on it yet retaining ownership, which is usually the case? I'd be very wary.
I am wary of any sight that asks for money for information that is free if you just go directly to the town that is offering the land. I am sure there are restrictions. I posted a few examples but like anything you have fine print.