If you use paid social media, you'll likely get the most bang for your buck using FB ads, though you need to take the time to learn how to do them well. 

Should I pay for the multi-family in cash or buy multiple apartment buildings by leveraging the proceeds from the SFRs?

You are also putting multi-generational family savings into one investment. 

Multi sounds good for the number of doors per loan.  

At first everything went well, we got together a couple of times to talk about the strategy that I was going to take to buy my first multi family (first investment property overall), but so far he hasn't send me any properties to analyze.

Unless you do a 180 turn in mindset your $500 K will soon be  a buck Fiftee.People who will connect with you are those who Want your 💰........ 

@Jacob Ketchum I’m looking at multi family houses or single family houses because that is what makes sense to me now.

House hack multi plex is not easy, I personally not want to live close to my tenant.

I am looking into purchasing my first multi-family property.

This area has some of the best schools in the state, relatively low property taxes, a mix of country and suburban property, and housing from 140,000 to multi-million.