After 4 pages of discussion, I still dont understand the issue.  Like I said, it is only 3.3% of the total cost!  It is the he says she says thing.  If you dont itemized all the changes with variation orders, then you can argue until the cow come home still can't resolve. 

I made it very clear to my subcon that any work started without me signing the variation order I will not pay for it because I would not have budgeted for it.  That would be the "free work" thing.  If you think that for RM150k, you can lump a lot of free work in there and without the clear understanding, then that's the issue.

give me the contractor's name and contact number. i settle for you.
just kidding of course. don't let the RM5k blind u. Focus on the WORK. Tell him to finished up the job and see the workmanship. If it's up to your expectation, then just pay him the RM5k for the good job he has done. Heck, you can even pay him more. Nothing beats the satisfaction of getting the renovation done nicely according to your requirement. After all, rich bloke like you sure can afford RM5k one mah

I am sorry ... may be I am stupid or something ... if the quote that he gave you clearly stated that the work includes building a staircase then it is part of the scope.  We have not seen your agreement but I would bet that your agreement did not included in the written scope of work.  Again, in my sub cond proposal/quotation to me he would spell out EXACTLY what is he doing down to what rooms being built, which surfaces will have tiles, how many light points/powerpoints, number of windows and size of the windows and type of the windows.  I just dont understand how can one argue on the staircase work being free or not.  Clearly it can't be free but if it is not written as part of workscope but verbally agreed as part of RM150k, then it is an issue.

BTW, I hope your real profession is not Project Manager, i would never hire you! 

Free stairs? Whether it is concrete steps or wooden stairs, it would costs quite a bit to build one and you think he should give it to you for free? Honestly, just pay up and treat it as lessons learn. Unless you feel you are a bigger bully, then tell him to go fly kite.

What do you expect people in LYN to help you? Guard your house and protect you from harm?

hahaha.  good one..

the problem is that he expects FREE things