I'll use simple yet realistic numbers for those who are not familiar with the Bay Area real estate market, Example Business - Real Estate Developer LLCLot Price - $1,000,000House Size - 3,000 Sq FtConstruction cost per square foot - $500Construction Cost = #2,445,000Total cost to Build = $3,445,000Sell Price = $4,500,000 Average square foot per area (Palo Alto and Mountain View) - $1,500Construction Cost BreakdownConstruction Cost @ $500 a square foot$1,500,000Contractor Fee 10% of construction cost$150,000Civil, Mechanical, Electrical and Structural Engineering & Architect Fee 30% of construction cost$450,000Permit Cost 1% of Home total value$45,000Site Work & Landscape 10% of construction cost$150,000Contingency 10% of construction cost$150,000Land Purchase BreakdownDownpayment 20%$200,00018 Month Mortgage Payments$95,000I know the land purchase will require a 20% downpayment ($200,000) and the construction loan will also require a 20% downpayment ($489,000).

Do you have a good architect or know one.  

If you are in CA and need some help or resources I know lenders, contractors, architects and consultants that are doing ADU's - Jut DM and will get back to you.

I have connections to Architects, GCs and Investors.

It involves working with equity, loans, buyers, sellers, mortgage brokers, real estate brokers, attorneys, title companies, insurance, municipalities, architects, engineers, and contractors.Role of the contractor is to build what has been specified for the agreed upon cost of the work. 

The other is a 3/2 mid-century modern (designed by famous Palm Springs architect McNaughton) on a commanding & very private 1/3 acre lot with views of Mt.

I wouldn't spend a dime on a real estate degree unless I planned on being an architect.

Architect, interior designer, or some contractors can provide a design, almost all will charge for design efforts.

Local Architect and BP friend @Nik Moushon inspected the house with me and provided excellent advice about codes and how they would apply as I attempted to change the use and bed count of the house.

You can find an engineer by reaching out to Realtors or draftsmen and architects.