Help, 10-15k dollar mining farm.

I took a loan of 125 000 NOK - 15000 ish usd.

I am thinking of creating a mining farm, do you think it's a good idea?

I have the space, power, and cooling capability.
Power is extremely cheap, around 0.01-0.02 KW/h ($)

I have some experience with mining, currently I have 2 rigs.

Rig 1: 6x 7970
Rig 2: 4x rx 470 4gb

I have a job to pay down the loan, so I'm not required to succeed.

What equipment should I buy?
Prices are a little different in Norway.
rx 470 4gb = 245usd
rx 470 8gb = 300usd
rx 480 4gb = 300usd
rx 480 8gb = 350usd

I'm thinking of buying
32 rx 470
8 mobo's
8 ssd's
8 ram sticks
8 cpu's
PSU's I'm not quite sure how many, or what quality to buy.

Then use the rest for shelving and cooling

Any thoughts?