But if you need to rent one and document results.You might look into some sound dampening material as well.Before doing all of this, in a non threatening way, best you can - try to develop a relationship with the neighbor so that you don't have to go down the civil adversarial road.....

You can get material to soften the sound of footsteps as well underneath it.Those stores you mentioned should be able to do the job for you

In addition to quality of materials, you want to appeal to the largest group of people possible. 

I had the trenching done by unskilled labor the drains were covered in a mesh material that I bought at Home Depot.

Still doesn’t add up to me so I’m going to hafta try and find out what really happened to all the money by getting contractor to send me invoices and receipts for material and try to reconcile that to bank account statements.  

It's hard to beat much of the free material on this website and the books published by Bigger Pockets for that introductory glimpse.

I am looking for any recommendations for a general contractor that I can use on all my future jobs that is reliable and investor friendly when it comes to materials and cost.

@Idan Narotzki Careful screening, strong lease (and strong enforcement of it), diligent move-in/move out checklist (so they know you’re paying attention), large security deposit (I ask for double 1 month rent amount which in my area means $3-5k), avoid Class C-/D, find a good collections agency that will work on contingency basis, make your units as tenant-proof as possible with inexpensive yet durable materials, hold plenty in reserve funds, set proper expectations, communicate well but firmly and treat tenants fairly and professionally, and be willing to clean up a mess and fix things occasionally rather than pay a company thousands to do it for you.

What is the proper way to add materials I purchase for the home build to the cost basis of the home, especially if I buy them before a.) breaking ground or b.) a calendar year before the home is finished and sells?

Here is a checklist for Getting Bids for your Project.Create a detailed Scope of Work for your ContractorsCreate a material list and define who is responsible for materials (you or Contractor)Finalize project drawings (if necessary)Call Contractors and schedule contractor walkthroughs to receive bidsEvaluate contractor bids and determine the Lowest Qualified BidderAward contracts to ContractorsRehab Prep After you receive Contractor Proposals, you need to finalize your Project Budget, Project Schedule & prepare for closing so you can 'hit the ground running' once you close on the property.