But you should still always insist on estoppel letters and right to inspect and approve all active lease agreements, and insist that there are no "side" agreements other than what are disclosed to you for approval after the purchase contract is signed.

I am currently in the process of having the house inspected by both an inspector and my contractor.

To actually make an offer I just call my realtor and tell her how much money, date of closing and any contingencies I want such as inspection. 

The real difference from the things you're describing is the difficulty in inspecting the lines exact condition, it's not like a roof or windows at all.

- dose appraisal process require home inspection ?

The homes are in move-in ready condition i.e. no rehab required or no major issues uncovered in the inspection report?

Be prepared to pay inspection and appraisal upfront and commercial appraisal aren’t cheap.

Around the same time, I began to discover self improvement books and of course happened upon Rich Dad.I have been steadily researching for all that time since, and trying to improve my station  and job expertise (pipeline inspection) to enable me to get real estate. 

You'll also need a contractor who is financially stable enough to pay their workers out of pocket for a few weeks at a time bc you will only be allowed a certain number of draws during the project after certain milestones have been completed and inspected.

Going forward we'll have an electrician inspect all properties prior to purchase with possible K&T, so we know exactly what we're getting into and can better negotiate the price.