Need advice cob configuration!

Ok I have now decided I'm going to build a cob, I'm no electronics whizz or diy expert very far from it but I'm sick of the temp swings with my hps and sick of trying to keep it under wraps. budget is around £250 I've looked at plenty of vids and done some research just want some ideas and opinions I have a 4x2 space so need a lil help with config what cobs and parts etc.. Please post what you would do and what parts prices etc would be much appreciated thanks again.

Here is what I would do (I have built several):

From @SupraSPL

@ 56.3%
(4) CXB3590 3500K CD 36V @ 1.4A (49W ea) $190
(1) HLG-185H-C1400 $65
196 dissipation W -> 85.7W heat ->
passive cooled heatsink 10284cm² -> 5.88" X 40" heatsink $80 (could split in 2 to improve uniformity/spread)
(4) Refelectors from Jerry ($3.20)
110.3 PAR W covering 6ft² = 824 PPFD
$311 = $3.07/PAR W passive cooled (great value point IMO, very efficient use of driver)

The above example uses a heatsink from heatsinkusa. Since you are not in the US, you can find a comparable heat sink at:
http://www.tme.eu/en/

You can order the Cobs and reflectors from Jerry or Cutter. Jerry also has the driver or source locally.

You'll need wire, screws, potentiometer, switch and a few other items. Watch the videos, read a lot, ask questions when you get stuck and have fun. These lights rock and are a ton of fun to build. Good Luck

Bonjour
You will find the cheapest heatsink in EU in tme.com but also all the other parts you will need for the same shipping costs (fans psu wires wagos TIM screws potentiometers resistor...everything at good price (you can even ask them to avoid the vat cause your are not a company!) And if you go with cutter you will need hlg driver they have some too (72 € with vat)
CU