I am 56 years old and am a senior advisor software engineer (computer programmer).

I would type in one of those search phrases, and at the bottom of the search engine results page (SERPs) that pops up with the result will be even more commonly searched phrases under, "Searches related to...."

I'm an engineer and I oversee them installed all the time.

I have a degree in construction management, and my full time job is working as a project engineer for a large general contractor in Seattle.

I have a background in engineering and also residential home repairs, as I am still in business with a family construction company.

It takes us a year to learn the market and develop a successful rate structure, then to integrate that into algorithms that we use to adjust pricing on the fly.

I'm a structural engineer by profession committed to finding my first rental property.  

Also, do a search engine check of "purchase and sale agreement" and see what comes up.  

I am a 27 year old single software engineer who just recently got more interested/involved in saving and investing.

Things such as average cost-to-build in your local market, the different types of construction possible (sip, modular etc...) zoning, cost for permits, engineering & geo reports etc...The second method @J Scott recommended is probably the truest way to evaluate the land cost.