I'm considering selling the property and exchanging into more units (still in L.A.) but I'm trying to decide between two strategies and would be curious to get others' thoughts.OptionA - Buy 4 fourplexes.

We have plenty of investors who invest in our investment fund using their SDIRA; especially now that the stock market is so high. 

It's all a question of time, expense and ROI for either of those exchanged.

I would like to trade my plumbing skills. in Exchange, to show me the ropes of investing and flipping my first house.

I have about 100k in stocks (retirement s&p) and I bought a 2 family house in May 2019 for 535k put down 20%, 30 year.

Maybe in your case you could offer some work in exchange for mentorship and build up to having an interest in the deal.If you haven't already, I'd definitely attend local investor meetings - that would be a great way to meet people and potentially learn about people/organizations who could offer you lots of experience.  

All I need to do is deploy the savings into a new property or simply reinvest the money into the stock market for a higher return over the long term.

I remember a staying Warn Buffet said buy stocks when the market is down you are getting them at half price (something along these lines). 

But I'm hearing about the corona virus stuff, how the stock market had the biggest downfall right now, and I'm just worried that in a few months, this property will be worth half of what I would pay for it.

Stock market, real estate market?