You definately need a plumbing permit too.I do lots of rehabs, some areas are easier to squeak by then others.  

If one inherits tenants from a previous owner, is there a limit to what is defined as a lease.

Also, more a question due to my lack of experience, since this is a list of the outstanding tax sale leins, I an only assume that there is a list out there that defines the properties that are late in their taxes, but have not gone to a tax sale yet.

The land contract is defined by you the buyer and the seller.

Could you please define the difference between this too different types?

I think you need to define your expectations first.

I am not worried about robots replacing humans since advancing technology always seems to create as many problems as it solves, and while AI can solve problems whose parameters are well known, I don't think it will be able to solve new problems where the parameters still need to be discovered and defined.

Define what it is what you want to do otherwise it will be almost impossible to know who should be on your team.But, hey, just one opinion from an out-of-state investor sitting behind his iPhone in California! 

Just as a business benefits from defining their Mission, Vision and Values, so does a family.

What precisely defines those criteria is based on individual facts and circumstances, as indicated by the courts and IRS.