I've always felt that when it comes to entering the Never Never, there's gates and then there's Ways. From how they are used, it appears that Ways behave differently from Gates in that an established Way works the same for everyone, whereas a Gate is trickier.
When it comes to defending his house from Never Never incursions, it seems Harry's method was to try to avoid making his house the exit of a Way. Instead, he seems to have relied on the inherent instability of Gates (this could be one possible explanation for why Harry's place lead to different Never Never locations in Grave Peril and Changes) to make it harder for his enemies to attack him (since they would have to spend the effort to find out what new spot in the Never Never corresponded to Harry's house at the time of their attack).
Meanwhile, both Lea and Corpsetaker appear to have relied on the opposite strategy: turn the Never Never side into a Way, and fortify it as much as possible. Harry's hideout appears to be a compromise: since he's hardly ever there, he deemed it better to have a stable Way that lead to one of the safe paths through Winter used by the Council.
Of course, just because Gates are not as stable as Ways, that doesn't mean that one cannot find a path to their target in the real world. Both Thomas and Cowl accomplished it in White Night. I suggest that both followed a similar method, namely, using a tracking spell on someone on the Real World to lead them.
I've always considered Proven Guilty a good example of a story with both Gates and Ways. The closed cinema theater was a Way that always lead to a spot close to Artic Tor. Meanwhile, the mirrors used by the fetches in their other attacks are merely Gates, which means that when they escape into the Never Never, it's harder for other people to follow them.
The question is, what turns a Gate into a Way? We don't know for sure, but I would offer this: it shouldn't be that hard for the same beings that opens a gate in the same place in the real world (or vice-versa) to end up at the same location in the Never Never (or vice-versa) every time. Do it often enough, and you weaken the barrier between the Never Never and the real world (this is how Harry describes it in Changes) and a Way is made. This could explain why Harry managed to open the same Way she did, since I think it's fair to say Harry was more in common with Cowl than with Agatha.
P.S. I suspect that Fae can discern from the real world the type of place a Gate (or a Way) will open to. It's something we see Lily do in White Night, and it's the only thing that would explain why Tiny the Gruff (considering how injured he was) would dare jump into the Never Never from the train station in Turn Coat without being worried about reaching the same place in the Never Never as the hobs.
