The cost varies by fit and finish. If you want wood, the type of wood, inlays, etc. I bought the three of them before they went to the show. In fact I have not even seen them until I saw them on the web. They should be here on Monday or Tuesday with the total freight weight of 837Lbs. The CRAZ4 rack listed at $8000 because it had more upgrades than normal. It had 1.25 granite on all shelves instead of only the top while the others come standard in .75. The two Ohio Class XL stands which are custom made for what ever they sit on (mine being Tenor 300's) list for $4000. They have special upgrades too. All three are said to be the best in total isolation.
I have the VR isoBASES (which were made for these amps) right now under my Tenors. In fact, I bought them from Frank Peraino who had them under his Tenors and upgraded to the Ohio Class XL. Before I had them I had my Tenors on the carpeted floor. The change was not subtle so I know they do what they are supposed to do. I am really looking forward to it when these three get here.
So, very soon like next week you will see my Zoethecus Z5 here on the gon. :^)
Michael