That is very doable. Good budget. You’ll be fine to selfhost. Proxmox on a desktop you build is the best all around solution imo. 

Here’s roughly mine, I think the ram I selected is different: https://pcpartpicker.com/list/8gDH9c 

 Oh and this is the case it’s in: https://www.amazon.com/AUDHEID-Enclosures-Compatible-Micro-ATX-Motherboard/dp/B09QKMQ1B1 

 Oh wait, I have 5 4tb evos.