- M.2 SDD : depending on your motherboard support (check interface whether : SATA or PCIE(2 or PCIex4): best price /performance for PCIex4 = Samsung 970 evo, (or 960 pro or 960 evo), optimum choice would be 500 GB, but 250GB would be fine: plenty of choices among top brands with comparable performance and some much cheaper options.
- Bulk SSD around 150$: Crucial MX500 or Samsung 860 evo.
- You could combine a larger 500GB M.2 SSD with a 2TB 7200 RPM performance hard drive if budge restricted and not tower space limited.