I will be putting about 10K as a downpayment and want to grow a real estate empire.

This way your empire can grow quickly and your risk can remain minimal as you build your portfolio however you wish.

Our goal is to build a portfolio or as I say an "empire" of passive income to provide the cash flow needed for early retire in 15 years, wo we do work on furthering our careers.

“If you want to take the island, burn the boats”Alexander the Great, who created an empire that stretched from his home in Macedonia to India, ostentatiously burned his ships when arriving in Persia in 334BC.

Can you really create a massive real estate empire in a short time when starting with almost nothing?

All of these were homes in the Inland Empire, built between 1990 to 2000, or later, so very little deferred maintenance. 

Nothing very high crime in OC anymore, but parts of south LA, Compton, Watts etc are still fairly high crime but are seeing real growth and improvement that might make it worthwhile, as is of course city of San Bernardino and a number of other areas in the Inland Empire do offer this sort of thing.

I'm not building my 'empire' quickly.

Having a great agent/broker can also allow an investor to scale and grow their empire/portfolio in ways that they never anticipated or dreamed of. 

Congratulations on your real estate empire!