Probably I will spend much less for the workout room that I tentatively plan to set up after ER next year and my move to Missouri. But I plan to buy equipment one item at a time and to build my home gym over a period of several years. I'll start with a high quality treadmill and TV, and see how that goes. If I find that I do use it consistently, then I might get an elliptical, Bowflex, and/or set up a stretching station eventually.
My present gym charges less than $600/year for a full, unlimited gym membership. At an SWR of 4%, that would be equivalent to a lump sum of only $15K. I have access to far more equipment than we are talking about in this thread, all top quality, and the gym maintains and replaces it as needed. Plus, there are several indoor pools, whirlpool, steam room, trained personnel to ask questions of, and dozens of classes available. The main disadvantages are that hours are limited, and I have to drive several miles over the interstate and down busy streets to get to the gym. When I move to Missouri I don't want to have to drive in the snow and ice just to get to a gym every day. Maybe I'll end up living close enough to a gym to walk there. That would be ideal.
The OP wants his home gym to be completely set up right from the start. I could see spending $30K on such a setup, if I was sure that I would use it consistently for the rest of my life. If it makes him happy to be able to work out on the best of equipment at home, why not? Some ER's spend money on international travel, and others may prefer to spend money on a home gym.