What are the pros and cons of a double height ceiling 6m +

Does it really keep the room cooler?

And what about size of AC unit and the increased cost of electricity consumption that comes with a large AC unit especially if there is a gallery at 2nd floor level?

Changing light bulbs, cleaning windows and opening and closing blinds and curtains at high level?

Effect on home theatre sound systems?

Is it worth it?

This query seems like comparing a BMW 6 series with a Honda city and asking if the former is worth it.

If you enjoy a duplex and can afford it, go for it. Technical problems can be resolved with some cost and time.

Our living room reaches up to 7m, for the purpose of not requiring AC in that area. I find that home theater and computer room works better with a more normal ceiling and AC to cool down and dehydrate the electronics. You will need a special ladder for changing lights after the initial bamboo scaffolding is taken down. Some may find it wasteful but a high ceiling really adds to the feel of a place. Worth it if you can afford it.