I'm setting up to have a structural engineer review the property which i've never used before they run about 850-1000 for the inspection and will give estimates. 

Planning to do about 1,600 sq ft of engineered hardwood. 

From my experience with other construction projects and some research I've found its Purchase, Hire an engineer and surveyor to write up a proposed subdivide that I will then have to get approved from the city/county depending on the lot.

As an engineer, I love seeing the number and progress.

Just using Zillow rentals to reverse engineer potential areas (i.e.

The owner had a structural engineer come inspect it, and they recommended removing the tree and having the foundation remediated.

Real estate development is super expensive, can't I cut the costs by just opening my own construction firm, paying architects, engineers and all other professional figures to do the job that the construction firm would do without paying additional money than just labour and primary materials?

Then you can reverse engineer and come up with some options.

LA is so diverse and there is a wide range of finishes (laminate versus engineered hardwood versus refinishing for example) to choose from. 

Buy or inherit and hold all their lives while working the properties for income.I've seen teachers, firemen, software engineers and all sorts of people utilize both strategies successfully.