Get an upgraded 2012 mac mini for $170, and a 2020 MacBook Pro with the good keyboard for $650.

https://www.ebay.com/itm/185887440155

Or get a beefy server with proxmox for VMs, but still, you need a laptop.

bitcoin

Use cheap laptop for connection to good PC at home?

Get an upgraded 2012 mac mini for $170, and a 2020 MacBook Pro with the good keyboard for $650. 

Ultimate minimal setup.

Edit: links
https://www.ebay.com/itm/185887440155

https://www.ebay.com/itm/234815564387

Edit: 

Or get a beefy server with proxmox for VMs, but still, you need a laptop.