The size of the house is a factor that can influence the cost but sometimes size doesn’t matter but sometimes factors i will list below.

The cost of building a House of same size in same location and same land can be double if not properly planned.

Number of doors and windows can increase the cost of a house.

Rather down building more rooms. Double big room should be a better idea. Mistake people make is having more rooms which may end up not in use.

Building giant decorative pillar’s and unnecessary design and beauty.