Following on from this, if you don't need the latest hardware (i.e. you are currently using a laptop as your main device), you can buy used workstations on eBay

Following on from this, if you don't need the latest hardware (i.e. you are currently using a laptop as your main device), you can buy used workstations on eBay rather cheap. At the end of 2016 I bought a three year old Dell T3600 with 32GB ECC RAM and a 8c/16t Xeon E5-2670 (Sandy Bridge) processor. I just threw in a modern graphics card (GTX 1060) and SSD, and it's perfect for my needs. Total cost was under €600. I still have a laptop, so if I'm out I will just SSH in to work.