You are getting ridiculous now. Training this on "Taobao product photos" will lead to a useless model that is unable to produce practically all of the "cool" demos posted here in the last week.
As of about a week ago this tech runs on consumer GPUs. The weights have been downloaded 100s of thousands of times, and fine-tuning / modifying is possible.
Training from scratch is about $500k still, but it will only get cheaper and easier.
But I would not be surprised if this was trainable on a commercial GPU at home within that time. But I think another important trend that we are seeing is that you don't need to train these models from scratch.
Open-source "foundation models" means that you can usually get away with the much easier task of fine-tuning, as to not throw away / re-learn everything that these large models have already fit.
Edit: I initially said 2-5 years, but on more reflection this does seem optimistic (for training from scratch).