The thing is, I don't expect I'll necessarily have this kind of space forever (and almost certainly not this particular one), so it's hard to justify things like cutting a hole in the side of the house to crane in an industrial lathe. I'm planning on getting more hobbyist-scale stuff (though still space-consuming) with a goal of using it to build my own, smaller, portable workshop (a small lathe, provisions for using it for milling, a selection of cutting tools and the necessary meta-tools to maintain them, a pack-up forge/foundry).
The ultimate dream is something the size of approximately a (possibly large) suitcase or footlocker that can be used to recreate itself (think RepRap but a whole, miniature machine shop), so that I can 1) continue in my hobby even if I have to move into an apartment, and 2) share this with other people by helping them bootstrap something similar. The David A. Gingery book series ("Build Your Own Machine Shop From Scrap") is my inspiration here, though so much of the series would be a lot easier if you could start with some existing machine tools instead of having to do literally all of it from scratch).
I started in an apartment with the small Shurline lathe and mill and they were quite fun and capable for their size.