Should I use online services like LegalZoom? 

As the local governments struggle to manage tax payer money responsibly, they should really offer incentives to private builders to build "income restricted" at a much lower price. $220-$300/ft for vertical build costs.  

My long term goal at the end of my investment journey is to enjoy the journey, play the long game, and  have enough income from my investments that keeps my family well and financially independent.

@John Mason, lenders will look at your credit history, income and assets held to determine your eligibility for a 15% down payment conventional loan.

Remember also that the interest on the loan is taxed at ordinary income rates.So for example lets say you have 100k and were making 8% in the markets - 8k per year and say you are in top bracket, you will pay $1600 in taxes per year or netting 6400.Now lets say you did a loan and were at 5% you are earning $5k per year (actually less because principal is being paid down and some of money goes into essentially a 0% checking account).

I checked online and I did not find any standards/rules.The lady in the unit 2 facing the construction is working in the office most of the week and she pays a rent of $ 2750 per month;  we agree for a $ 300 rebate when we signed the lease few months ago.

It served as my primary residence & rental income for a few years.

Can I then treat my property as an investment/income property?   

It served as my primary residence & rental income for a few years.

You should do a careful financial analysis to see how much rental income you might make compared to the expenses and potential challenges of being a landlord in California.