I work for an engineering firm. Both contractor and engineering firms spend a fair amount of staff and dollars in developing cost estimating tools and adjusting these based on market conditions, trends, and geography. Cost escalation and unknown conditions (surprises) are typically the two biggest risk issues. I am talking here about municipal and industrial construction in the order of $30-250M contracts. However, the same applies to residential construction, whether you talk about 1 or 100 houses. You can have a boilerplate estimate, but you will need to adjust it accordingly to take into account contingencies, unkowns, delays, material cost escalation (there continues to be volatility in rebar, copper, and aluminum), site conditions, etc.
Anyways, my point is that you can get a software that will spit out a number from quantity take-offs, the number (s) will then need to be adjusted by trained eyes to reflect the reality of that specific job.
Cheers.
JGA.