. :) I dont really use the high limits really except on my primary business card.

I'm always conflicted with whether I should leverage my primary residence for the sake of investment properties.

My plan is to use my HELOC from my current primary residence as the down payment.

I have a primary house in Santa Maria CA that we are renting out and getting cash flow from it,  thinking of using the equity from that house to buy here in Orange County.

Primary residence capital gain $250,000 exclusion.  

You could 1031 out of the property, purchase a new one or something you might like, "Live" there for two years and convert the property to a primary residence. 

You have two properties, one of which is your primary residence.

It currently seems I’m not going to be coming back to the states anytime soon (given the upcoming projects within the next 3-4 years) but would really appreciate any advice on investment rental property strategy as so to start building the foundation for generational wealth/passive income.We have saved a substantial amount of money  for which the original intent was to buy our future primary residence with all cash if/when we moved back to the states.However, that’s not what’s going to build generational wealth and would rather put that money into passive income investments hence, real estate rental properties.

So much so, that according to AirDNA data there are 4000+ properties on airbnb / vrbo in this destination, though the property that I am evaluating has been used as a primary residence and has no rental history.

Most will be 30yr fixed, but you're still going to need 20%+ down and will be 1-2% over what you see quoted as "today's 30yr fixed mortgage rate", which is usually the ballpark for someone buying a primary with 20% down and 780 credit.