I would not do a quadfire setup......advice over the years has been that AMD multi card setups was improving bit never venture beyond two cards. Then recently what many reviewers were reporting subjectively for years was finally proven in benchmarks:
http://www.anandtech.com/show/6857/amd-stuttering-issues-driver-roadmap-fraps/6
http://www.tomshardware.com/reviews/graphics-card-benchmarking-frame-rate,3466.html
At the beginning of August AMD relased new beta drivers which did a whole lot to address the problem. But, the prevailing sentiment still is they ain't quite "there" yet.
http://www.anandtech.com/show/7195/amd-frame-pacing-explorer-cat138
http://hardocp.com/article/2013/08/01/amd_catalyst_138_beta_frame_pacing_crossfire_driver/#.Ufsxbm0piX8
So for the immediate future, i am not prepared to recommend Crossfire.
As for SLI, I would recommend no more than 2 for single monitor setups ....and certainly no more than 3 for 3 screen setups. The 770s would be my choice..... NOTE: when ya get to 3 card setups, after a game comes out, ya generally gonna wait a month or two for nVidia to get the driver kinks worked out ..... until then you may oft get better results using 2 instead of 3 cards.
Start here to see the benchies
http://uk.hardware.info/reviews/4440/12/nvidia-geforce-gtx-770-review-incl-3-way-sli-and-frametimes-battlefield-3---1920x1080-+-frametimes
here's a 3 screen build
Case - $250 - Phanteks Enthoo Not available yet
PSU - $130 - Corsair HX850
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139011
MoBo - $300 - Asus Maximus VI Formula
http://www.newegg.com/Product/Product.aspx?Item=N82E16813132038
CPU - $340 - Intel Core i7-4770k
http://www.newegg.com/Product/Product.aspx?Item=N82E16819116901
Cooler - $80 - Phanteks PH-TC14
http://www.newegg.com/Product/Product.aspx?Item=N82E16835709011
TIM - $7 - Shin Etsu
http://www.newegg.com/Product/Product.aspx?Item=N82E16835150080
GFX - $480 - MSI GTX 770 4GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127747
GFX - $480 - MSI GTX 770 4GB Same
SSD - $250 - Samsung 840 Pro 256GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16820147193
DVD Writer - $54 - Asus Blue Ray Burner
http://www.newegg.com/Product/Product.aspx?Item=N82E16827135252
Monitor - $260 ASUS VG248QE Black 23" 144 Hz Monitor
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236313
Monitor - $260 ASUS VG248QE Black 23" 144 Hz Monitor
Monitor - $260 ASUS VG248QE Black 23" 144 Hz Monitor
$3,291
If ya want tri SLI, upgrade MoBo to the Maximus VI Extreme (+100), PSU to the Seasonic X-1250 (+$110) and add a 3rd GFX card (+480)
If ya want water cooling, set aside $600 - $2000, depending upon how fancy ya wanna get