the 24 hrs estimation that it  shows on the pool status, is that what each machine should be able to obtain if running the right parameters per 24 hrs? or is that the combined amount found from all machines in 24hrs. thank you for having zpool available i end up there all the time 

Where you shipping from?

exhaust looks good, I would put up a barrier wall on the back of the s9's. don't seal it off but block the air so it can get sucked out by the exhaust fans. I would add cool air inlet fans on the opposite wall to allow more fresh air in. 4 s9's per 30 amp breaker with 220v, highly recommend a nice industrial power strip like a 30 amp knurr server strip. any more questions feel free to ask

3500 cash For both machines, I can pickup tomorrow

was in the process of ordering two, until I received a email 10 hours later saying they are no longer available. this was after I submitted my info.