It depends on what you want to invest in.

The idea of debt-free is that if a person is going to retire and has to completely depend on the income, they don't want a severe recession surprising them and causing them to default on the debt and losing the properties.In a normal world, I would do that as well.

I would still do due diligence such as whole property inspection, lead inspection (depending on when the property was built), appraisal, etc. 

That is often a matter of opinion and will depend on the attitude of your municipality.Most municipalities do not require neighborhood approval, but will offer the public opportunities to provide input which will be considered.

depending on how backed up the county is it can e take a few months for court date. in essex county it took my mother in law about 8 months or so for the full process. she had an attorney, not sure if that sped anything up

For a smaller piece like that, not sure how creative you can get, but it all depends on what it's zoning is, access, proximity to other things, etc.  

I think you can go as high as 15% but it's cutting into your margins and depends if you are a GC yourself or not. 150k is close to a million or more.

I am starting the legal process as we speak and depending how many more we can make this a class action law suit. 

A lot depends on your entry price and instant equity. 

Depends on if you have panels, crazy layouts, etc.