Then they'll charge an additional $2,400 for filing tax returns. 

Account ClosedAdding your property manager as "additional insured" is standard practice and beneficial for you.

Additionally, I would like to attempt to do the process Owner/Builder with subcontracting work out as well as doing some of the work I'm comfortable with (I have some experience with bathroom & kitchen remodeling an am not new to the construction industry).

My goal is to leverage that equity for additional income.

The landlord should be named on the tenant's insurance policy for additional protection and to assist with tracking compliance.

I am considering building up on my fourplex. 2 additional units.

There should have been change orders alerting you of the additional charges, which would have given you the opportunity to make budget decisions.Check your management contract and check all your conversations with the PMC.

If you sell a property, and do a 1031 exchange with the proceeds, but don't need all the proceeds for the down payment of the next property, are you taxed on the additional profit that isn't part of the exchange?

That would be a helpful addition to your plan as you would further reduce your cost of living.Also don’t forget from that $600 you are planning on getting in cash flow you have taxes, insurance, maintenance, capex, and vacancy to consider.With two homes, you may want to keep that extra $20k as an emergency fund rather than spending it on a third property and then be left with no emergency funds.

The truth is, a good host will spend time managing each rental.