I'm a beginner in Italian so the question is somewhat basic.
I previously thought that there were two possible word orders for question sentences:
1) When person asking makes an assumption about the subject, the word order stays the same as if it was declarative sentence (subject first, then predicate) and only voice intonation changes:
La casa è vecchia?
2) When person asking doesn't try to make an assumption about a subject and wants to know about object's quality, quantity, location, etc. (predicate contains interrogative pronoun and goes before the subject):
Com'è la casa?
But then I found a question sentence example in a textbook that doesn't comply with standard word orders:
È vecchia la casa?
Even though that word order is not "classical" (predicate is ahead of the subject, but without any interrogative ponouns), it doesn't seem to me to be completely non-legible. I feel like this word order might be used, depending on what is emphasized in a question. Like, word order gets as in "La casa è vecchia?" if person asking assumes that subject (house) has a quality of 'age' and only wants to know whether house is old or not. Whereas in "È vecchia la casa?" the person asking is not sure if subject can have quality of 'age' at all and allows possibility of subject having other qualities, while still asking about that exact quality.
So, the question is: is such word order (as in the last example) legit in Italian questions? If yes, what function does it perform?