The second category is my personal favorite - bought a used and slightly beat up Nikon FM2n when I was in college for cheap and the thing is still trucking with no maintenance done 15 years later. Shutter speeds seem at least reasonably accurate and it only requires a battery for the light meter. All mechanical otherwise.

Or if you want to get fancy the Nikon FM3a gives you sort of the best of all worlds (all mechanical internals or battery powered auto exposure with the flip of a dial)