@Lolo Druff Real Estate Investing is not like Trading Stocks or Crytocurrency.Real Estate Investing requires some deep thought and research from you as an Investor.Having 400k to deploy to multiple duplexes is a great start but you have some questions to ask and answer yourself.

I want a specialist that's an expert, and not a jack of all trades and master of none.

After the first year of renting them, and if their values have risen enough, I'll "trade up" for something else with a higher cashflow (assuming I go for a higher downpayment.) 

The HML/PMLs generally have more "flexible" or "creative" lending terms (higher LTARVs and longer amort), but the trade off is higher interest rates.

Bitcoin trades 24/7, with a click.  

In the future when I start trading up to larger properties (50 to 100+ properties) I will likely sell off my current portfolio to condense my holdings to fewer parcels so that way my time is better utilized. 

Both can align with your goals—just weigh the cash flow vs. upfront cost trade-off!

They started trading hand written IOUs for food.

Using a GC you will have less headaches as you'll have one point of contact and they will coordinate schedules between the various trades. 

Be sure to utilize tools of the trade for the best information.