I’m sorry to hear about your predicament. I’m going to keep my comments brief as your case is that unusual I think it would pay for you to take professional legal advice.
Your landlord sounds like an absolute grade A douche-bag, and if I were you I would try to find any legal means to back out of your tenancy agreement. The offer for you to buy out his short-let that means you can’t move in on the date to which you are legally contracted is just jaw-dropping in it’s crassness, even by the standards of some of the the Singaporean landlords we often hear about here! If this is how you’re being treated before moving in.... well, it’ll only downhill from here.
My gut feel is that the previous tenants maybe lived there quite a long time. When they were moving out the landlord probably dicked them over on their deposit, and so ‘to get their own back’ they stripped out every single thing of value that they had added to the property
. Now the landlord, rather than lose face, is expecting you to pick up all his losses.
What you’re facing is like bait and switch with a bit of blackmail thrown in too. I don’t see much point commenting on the individual expenses you mention, I really think you need to see a lawyer ASAP (before your original move in date!) to consider the situation as a whole.