A big open workshop with separate work stations, a partitioned area for resin work, shower curtain style dividers to contain majority of dust and shavings, especially around the lathe. An even bigger temperature controlled space to store my woods.
As for tools I'd probably go with new equipment, obviously a big lathe with all accessories, multiple chucks for anything I'm ever likely to need, full range of turning tools, 2 bandsaws because im lazy and dont want to change out blades if I dont have to, one for rough cutting/ripping and one for more detailed/accurate work, a whole station for shaping and sharpening that will probably have 2 or 3 bench grinders with different grit wheels and a Robert Sorby pro edge.
As money is no object there's one thing none of you seem to have considered, an assistant to help and keeps everything clean and tidy in its place.