This is not for everyone. Not plug and play. You will need some DIY ability to get this done.

if you have some DIY ability and don't want to pay $799+ for a quietcool whole house fan you can get this gable fan made by quietcool and make your own whole house fan for less than half the cost

step 1:
get this quietcool gable fan here on ebay

QC Manufacturing Inc. AFG PRO-3.0 QuietCool 3013 CFM Professional Attic Gable Fan
http://www.ebay.com/itm/252421456916 [ebay.com]

get 20% from the seller automatically
stack another 20% using C20LABORDAY

Item (1) $200.83
Shipping Free
Sales tax $10.04
Discount -$40.17
Gift cards, coupons -$32.13
Order total $138.57 ($128.53 plus tax)
step 2:
buy 16"-18" flexible duct
~$60

step 3:
you will need some misc parts depending on how you want the fan setup
~$20-$50

some videos of people DIYing their whole house fan

https://www.youtube.com/watch?v=6P0I6dG0c3g
https://www.youtube.com/watch?v=KVsUe7sOCPo