Some like to have a mid-day nap and active all night. My case not so serious but he's MR DIY, likes to drop hammer, nuts n bolts around 10AM. Then walks with heavy feet and also moves furniture around... I have to counter it by playing music so at least the noise made by him won't affect me much.

Its called water hammer..learn some science will you.
People said its a ghost as a joke. No one dragging chair after 12 am for no reason everyday.

u both leaving at ppr is it? that is why floor so thin.

Yes already did, the very first day I moved in this April, they already drag from morning till night walking nonstop dont know doing what, out of kindness, we decided to go up and talk to them nicely, what they replied was just "ok we'll try" then continue doing so.

After that one of the tenant brought guest over. they were like keep dragging the chair I dont know why, I went up around 3AM and their door was open wide and chit chatting loudly there.

But after numerous of complaints, they're still like that. Management also cant do anything, what management told us was "We already told them not to make noise, if they're doing still, what more can we do?"

I even met with their owner, turns out to be their friend, with super arrogant tone and told us "As you know this place only cost 300k so the flooring is very thin one" So what?? That doesnt mean you can make noise like that right?? I even showed them the sound recording, and promised that will buy the chair pad but they didnt!!

I agree, but developers just dont care, they want to build it fast and with low cost, they dont even care about parking space d (condos nowadays comes with only 1 carpark). So I doubt they will make flooring thick 
So just pray that we get civilized neighbors. Like I said, we quiet people, past dinner time usually sit down watch tv or laying on bed etc, but I just dont know why some people gets so active at night, so inconsiderate.