Well, since the builder says it's broken in, when it's delivered to you, put a finger in one of the exhaust ports on the head and wipe. If it doesn't come out with some carbon on your finger tip then the engine hasn't been run. That would be concerning.
Assuming you come out with a black finger, shoot for having it in a car within six months. Anything longer than that and I would take anti-rust precautions. Turning the crank bolt a half turn every three months would take care of the valve springs, but I don't even know if that's really necessary... but it would give you something to do instead of just staring at it.