Well, this is a DIY site..........so, Doing It Yourself saves about 85% of the cost of a new project since LABOR costs are most of the expense.
As for materials, most big box stores have areas where things like carpet remnants are cheaper than buying from the roll, mis-tinted paint is just a few dollars per gallon. For appliances, check for "scratch and dent" items. Local Habitat for Humanity Restore shops, Hospice shops, and Salvage Yards/Stores have used items of very high quality, some may even be new. Lots of ways to save.
P.S. Of course, none of this may apply if you live outside of the U.S. which it appears that you do.
If you are posting from India , few here are likely to know the specific "protocols" that apply . I have known what it's like to be short on funds , though , & the universal method of getting things done "on the cheap" involve compromising your demands & scrounging what you can find .
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