Go raibh maith agaibh! Funny how a simple little sentence can have several things to teach me. When I said “There is a house there” I think I was too tired when I posted (so it was redundant). I meant more like “A house exists there”, which still isn’t the best English. The other examples in Learning Irish which had “Tá…” seem to be translated as “There is…”, so it makes more sense to me at this point in my learning to think of it as “There is a house there” (in the sense of “a house exists in that location” as opposed to “there is a house way over there”).
I’d learned about “ann” and “ansiúd”, but thanks for the reminders as it’s all still new to me. I hadn’t come across “an” or “thall” yet, so thanks for that too.