ATM around 1100Mhs is needed for 0.1 Eth per day
Around 20 x Radeon 5700.
So 20 x 0.120kw/h * 24= 57.6 kw/day for the GPUs.
Overall i would say 3 rigs with 6 GPUs coming close to your plan.
I wonder how much money he needs to prepare to buy that hardware because I am sure that it would not be cheap as we can think. He needs to calculate the electricity fee before he buys the hardware, so he can know how big the money to invest in the investment side.
when you mine, you mine to hold your coins and take a gamble they will reach multiples of what the current price is. if youre mining to pay your electricity bill, dont bother
As long as he can mine the right and potential coins, I think he is not gambling with the coins.
@OP, you can try to check by yourself what hardware or GPU you need to buy at
https://whattomine.com/I try to use Vega64 and Radeon 5700. In Vega64, you need about 35 VGA card to make 0.1 eth/day, while you need to buy 27-30 VGA with Radeon 5700. So you need to think about the money that you will use. You can search more if you want on that site.