It’s mind blowing you can buy this on Alibaba. I love it.
That's just for hardware. Chemicals, electricity, factory space, and employees to run then probably multiplies that a few times over at least.
The actual construction of the fab will be far more important than all of this.
Just rent or sublease an old one. Clean room + water supply + waste processing facilities are not that uncommon. They have the most famous chip designer in living memory as their founder, finding a fab should be the least of their concerns.
No clean room if you read his Twitter replies.
The location of the Fab is also important. Seismic movement affects the process.