The next stop was to be a meeting with the land developer, but the person I had to meet was busy, so made arrangements to drop by later. That allowed time to have a look around some other displays, so the others went through the two large-ish displays Metricon had open at Craigieburn, while I got talking to the sales guys.
Their attitude was a whole lot better - and started from the right way, with a "how much would you like to spend?". Giving a "ideally $360, but max $380", that gave a good starting point, with the rep able to say "okay, here's some options to make that easily doable".
The design we mostly started talking about happened to be one they had on display and I'd been through, albeit a smaller version - the Delta 24 being the one on display, and the 19 being what we got talking about. They were able to also find a lot for that to fit on with a listed price, so that when I went to talk to the developer I could details on its location etc.