Mobo+CPU: Asrock B450M Pro 4 + Athlon 200GE: $202 OR Ryzen R3 2200G: $272
RAM: Klevv Performance Series 2666MHz CL16 8GB: $85 (Check ur QVL to see if it supports, i didn't check for you)
HDD: Seagate 1TB 7200RPM: $58
PSU: FSP Hyper K 600W: $79 OR Coolermaster MW 550W Semi-Mod Bronze: $79 OR EVGA BZ Series 500W: $69
Casing: Tecware Nexus M: $49 (Lazada)
Total: $463-$543
Good enough for web browsing, videos, your Microsoft Office needs. Can probably play Fortnite on 1080P lowest settings and maintain >30 fps
Future want upgrade can just toss in another 8GB 2666MHz ram. Or even a cheap GTX 1050 Ti or something. Can perhaps play games like Overwatch / Fortnite already.