Using flubit is easy, google for site, create account it's free. You copy a link from Amazon into site and wait for your personal offer and buy, pay by credit/debit card.
Anyway if I had your £1000 and must have's you highlight then this is my build list, from current prices.
Bare in mind the normal price for the CM 690 III is £75 - £80. I went 256GB on SSD as my OS with office/other apps & utils/benchmarking SW takes up 80GB. The Raijintek Ereboss was tested on an i7 4790K @ 4.4GHz with 1.275v vCore and got very good review in Custom PC Sep 14 issue. Here is link to earlier test on Link:-
Bit Tech
Even without Flubit the build is within budget by £150 -£170 but missing a projector/monitor/tv. You end up with great semi modular PSU, GPU you want & CPU, SSD, mobo with CF/SLI and SATA express, M2 slot and 8 true phases. Link:-
Do read this review on case, now with spare budget you could add extra fans or opt for AIO cooling later if temps an issue.