He backs this up by promising to file lawsuits against localities that prohibit permitting these projects.

The City of East Cleveland and its known issues are prohibiting new growth heading into their direction for the time being.  

I was shocked to learn that the tax implications of flipping property in New Jersey could make it cost prohibitive (eat of most or all of the profit).

For example if there is  noise or on street parking that is prohibited they should complain to the police.

They prohibit more than one FHA mortgage at a time with a few exceptions. 

., Under federal housing law, it is legal to not take Section 8 because there isn't a provision prohibiting discrimination based on source of income.But yes, some municipalities/counties/states have laws against it. 

We had to walk away from a fabulous house which was "unofficially" made into a 2 family years back, and current zoning regs prohibited making it a legal 2 family house.

Ability to buy in some neighborhoods that will not sell directly to investors (although rentals are not prohibited)5.

A: In a statement issued by the Housing Authority of Cook County in connection with the consideration by the Cook County Board of whether to prohibit discrimination based upon a prospective tenant participating in a housing choice voucher program the Housing Authority of Cook County stated as follows: “Owners still have the ability to screen all applicants for suitability for tenancy, applying their screening criteria – criminal background checks, credit checks, home visits, landlord references, etc. – equitably amongst all applicants.

You have to be aware of, and follow the rules to avoid prohibited transactions (which isn't that complicated).