RM3k to RM40k is a HUGE price difference.
for 4,300 sqft I would expect the price range to be more like RM10-20k.
That is based on the quotes I got for a 2,200 sft Duplex Condo that ranged from Rm4k - RM9k.
Regarding Rm3K freelancer - I'm assuming your using the term "freelancer" to mean someone who works by day as an ID for a company and is doing some personal jobs on the side in their own time. This is correctly known as "moonlighting"
The correct meaning of freelancer is someone that is working as a self-employed professional without any ties to another company.
A few things to bear in mind with this "moonlighting" proffesional.
1) They are actually stealing business from their employer. Most employment contact bar this type of activity and courts will take the employers side when push comes to shove on this issue.
Imagine if your employees were also actually your competitor, is that very nice for the employer?
The reason I mention this is it shows the moral and ethical values of the person. So don't be surprised if when you are dealing with them they short change you or cheat you. either in $$$ or in not giving what they promised.
2) If/When something goes wrong, there is no superior or company to complain to, that moonlighter might just stop taking your calls and then what do you do?
3) the moonlighter often doesn't have the time or full resources that a professional freelancer or company has to dedicate to your project.
Now to address the RM40K quote? are they on DRUGS?
Ok lets assume their not crazy or on drugs, maybe they are including other services or items that the others arnt.
Eg they might be providing
1) Organising of contractors or trades workers.
1) supervision of certain parts of the reno
2) supplying some carpentry items.
Generally you only get what you pay for.
In Business a common practice in assessing quotes is to throw away the cheapest quote (assumption is they are cutting to many corners or it will be low quality) and the highest quote (assumption is they are overcharging or you dont need rolls royce quality) and then start negotiating with the 3-5 other vendors that have quoted in between the lowest and highest. Negotiation is on both price and quantity/quality of what is offered compared to other quotes.
If is 4300sqft built up, I used to charge 40k. About RM10 per sqft. But I charge low yat forumer RM5-6 per sqft depending on the requirement and drawings involve. So they are not on drugs if they can deliver.