How would you spend 10k for a 8'lx2'wx3'h Setup

[Pan]

I'd build the room the tank is in with a slight grade and a drain in it. Also waterproof/rubberize the floors. You will also need a massive water/change salt mixing station, you can buy big food grade containers from all sorts of plastic vendors among other places. Humidity control is a must especially with everything else you have in your basement. I would suggest dedicated electrical for the fish tank room with appropriate fault protections in place