Go to mongkok mtr portland street. Loads of tile shops that will quote you per square foot and the seperate cost of the work.
If you are using a contractor, he is going to add his 30 percent.
If the apartment has wooden flooring, could you not just keep it and find a professional to polish / varnish it until it looks new. That would save you a lot of money.
vinyl adhesive tile is also cheaper and fine. I used it in my office. Saves a bundle. You could do the vinyl adhesive and buy some nice persian rugs to put on top of it.
Marble in the living room ....its sliippery with just an ounce of water, hurts a bundle if the kids fall on it, and might stain if you spill something on it. ( my rented bathroom has a nasty brown stain from rust or hair dye on a beautiful slab of marble that I cannot remove.)
If you do want to put hardwood flooring...I would suggest two feet width of tiles near the balcony first, then the hardwood flooring. Past experience of storm water coming in and damaging the wooden parquet floor because it went right next to the balcony door.
Save your money of living in a demolition zone. Put nice adhesive tape on the cabinet doors or paint them, install a copper / stainless steel wall, invest in changing the taps, and may be give new floor tiles. Why bother ripping out the kitchen if its still standing ? rather than burn money .
3. customized wardrobes.
Do it if it is solid wood, and floor to ceiling, otherwise ikea does its job.
I would also suggest a raised flooring platform in your bedroom so that you when you go. in, you have to step up two steps and you would have loads of underthe bed storage.
4. worth investing in the bathroom but get chinese quotes , not expat quotes.
5. sliding doors (done that ) save space but doesn't block out the sound. Go look at loads of websites ....go look at cool bunk beds ....local ones are kind of very much the same.
6. aircon yes...invest in split aircon.
you could also have a raised platform in the living room which is super cool and again gives you more space.