I would suggest you hold off on that build for just a couple months.
If you don't need a powerful gpu, but it would be a nice to have, I would suggest waiting for intel 11th gen.
Those cpus will be equipped with Xe graphics which should be pretty powerful (I'd say, around the level of a gt 730 or so, which is not high end, but pretty capable they are comparable to the mobile MX330)
While AMD has cpus with good gpus in them today, the cpu is not good. so, good gpu, bad cpu.
So, say you go with the intel 11th gen idea, it will be something along this line:
i3 11300 - 130$
Cheap board - 60$
psu - cx450m, or similar - 60$ or so maybe? not sure on pricing for that.
Ram - depending on how much VMs you have, and what amount you need it will either around 30 dollars, or around 70 dollars.
you would also need a case, say a cheap one for around 80$.
throw some, backup a bit and you get around 400$.
You could do the same today, but change the i3 to a ryzen 3 3200g, or r5 3400g if it fits in the budget. both of which are not good cpus, but have pretty good gpus.
you could also go current gen (10th gen) intel, but that would also not be amazing, since while they have better cpus, it will be a worse gpu. (current intel intergrated gpu is bad.)