Most viewings follow the agent's script. These questions change what you learn, and a few of them have saved our clients from expensive surprises.
A viewing is short, and most of it gets spent on the things you can see for yourself. The questions that matter are about the things you cannot.
Start with why the owner is selling and how long the property has been listed. A listing that has sat for months is telling you something, and the answer is usually price, title or a defect.
Ask what the last twelve months of utility bills looked like. It is the fastest way to learn whether the house is comfortable without running the air conditioning constantly.
Ask what has been repaired and what has been replaced. There is a meaningful difference between a roof that was patched after a typhoon and one that was replaced.
Then ask about the neighbours, the association, the parking allocation, the water pressure on the top floor, and whether the street has ever flooded. Owners answer these more candidly than people expect, and the hesitation itself is informative.