Only sign something if you are prepared to accept the terms, otherwise don't bother.
Assuming that it's just wear and tear and not major damage, you could refuse to pay. Send them a letter requesting for deposit and take action with Small Claims.
Up to you if you want to admit to damage and negotiate on the damage amount?
Any photo's to support claims, check in vs check out?
Whatever the case, send them a letter by registered post.
On the top of the letter, write "WITHOUT PREJUDICE"
“Without Prejudice”: More than a Label | Hong Kong Lawyer