However, it can be at times a bit hard as the low-hanging fruit is gone and there's a lot of eyes (including institutional money) on the sector.  

My partner and I used hard money to buy property and have about 180k in house so far.

Hard money is something too scary for me to even consider. 

Two-story houses bring in more money from rent and make saving on costs easier, but buildings with four homes cost less to start and are simpler to manage.

Cities will either not be able to comply or select sites that are currently zoned and used for purposes other than housing.This can lead to more complications with lawsuits and other administrative challenges that in addition to absorbing time and money prevent additional housing units from being built.

AVOID syndicators (who will happily take your money).

They'll likely want you to use the money you're making on the sale of the lot to partially pay down the remaining mortgage since it will be for a smaller remaining amount of property which makes sense to me from their point of view. 

You might also consider maintaining a certain level of cash reserves to handle maintenance/capex as needed.The general point the author is emphasizing is that to reap the benefits of compounding you must reallocate your cash flows into the same or other cash flowing investments rather than spending them on discretionary expenses.

You're asking someone to spend a lot of time and energy to share what they've spent years - maybe decades - learning and developing.

I personally do hard money lending and investing in the city.