Hi,
I'm new here and need some advice. I have a very limited budget 
I want to start with Z390 AORUS MASTER & i9-9900k and upgrade it gradually, depends on a budget.
I will use it for AI, Photoshop, Premier Pro, After Effects. 
What is the lowest price fan for CPU? 
What is the lowest price graphic card for it? 
What is the best PSU for AORUS Master with i9-9900k? 
Need help, please recommend, please advice...thanks. 
This was my approach to building a Aorus Master / i9-9900K based PC...
1) Do your research first. I built a spreadsheet of every component for my PC, detailing prices for about ten on-line suppliers. This is the easiest way to determine what you are going to buy and from where.
2) For graphics (Photo editing, etc., but not gaming), I just transferred my Radeon R9 270X from my old rig. It still works great!
3) I went with the Corsair HX850i PSU, which is a good match for this combo.
Also, cooling is important since this CPU runs very hot. I went with the Corsair H115i PRO AIO water cooler. I would advise against the RGB models as they seem to have loads of issues (check the Corsair forums). You are also going to need a decent case (Fractal Define R6 is a great choice), and additional case fans (Corsair ML fans are my choice).
Some UK retailers from my list...
Scan
Aria
Amazon
eBay
OverClockers
CCL
Novatech
eBuyer
Awd-It
etc.