A1278 (8K 2025)
If you find one for under $120 with no cracks, install an SSD immediately and replace the thermal paste (it will be rock-hard). It will easily last another 3-5 years for basic tasks.
unless you are willing to use OpenCore. Do buy one as a dedicated Windows 10 machine, a Linux coding box, or a typewriter. If you find one for under $120 with