Nobody is throwing away VRAM in this economy. But a used local-AI rig can still be a real bargain. The opportunity is usually old server platforms and patient sourcing, not a magic GPU found in a dumpster. VRAM tells you what might fit. Memory bandwidth, CPU, storage, power, cooling, PCIe lanes, and software support decide whether it feels usable. DDR4 can still make sense. DDR5 should be faster. For some MoE workloads, a weak CPU can ruin the apparent GPU bargain. One builder reported assembling a Z440, 12-core/24-thread Xeon, 128GB DDR4 and mixed storage for about €250 over months. Useful lead, not a universal build recipe. Pick the model and the speed you can tolerate first. Then buy the bottleneck. Mixed GPUs and 150 t/s are stack-specific questions, not promises a parts pile can answer.