mini-itx build

Hi all, I currently have a Z77 i5 3570k desktop with a full size 1070 Strix card in a mid-size Coolermaster case. My monitor is a BenQ GW2470 24" 1080p. I play games at 1080p with most of the games at high to max detail with no intention to upgrade the monitor or the graphics card. Though the...

maximum $800 aud (approx 550 usd), no peripherals (windows, mouse, fans etc), mini-itx system (not micro atx) What's the best possible build for such a tight budget? Case: GEEEK A30 Aftermarket CPU cooler/exhaust fans to get (if needed, considering Noctua NH-L9i) are ideal to include but don't...

Before I am super lazy and ask someone to figure it out for me (yay) GEEEK A30, pretty little box. Though I have worries about the side panels, big open gap for dust and all that (is there a black version also?). Don't suppose it would be right to paint the side panels black, and add a steel...