Does this contract have to be drafted specifically for me or is there a general contract that will suffice.

Google Maps does not suffice for this, as a mailing address, or Gmap address may name a specific city, but it's jurisdictionally in another city or county.Example:This says city of Los Angeles, but it's really in the unincorporated county of Los Angeles.This difference is critical, as all zoning regulations are specific to the city or county that your site is in, and every city's zoning codes are different.

A bank statement would suffice.

If I were to be approved for the loan and I start paying it off (on time), wouldn't this suffice for raising my credit score? 

The due on sale clause after title transfer scares me so if I'm not using an LLC will opening a second separate personal checking and savings account at my current bank suffice for bookkeeping purposes or is it still preferable to open a business checking/savings account?

Is there a 1:1 ratio or does one LLC suffice? 

Should we consider a real estate attorney to draw up the contract or will a standard purchase agreement with a separate agreement that outlines those details suffice?

If this investor needs $4000 per month income, then 8 rentals generating $500 per month cash flow will suffice, or 10 properties each generating $400/month, or whatever multiple of cashflow and volume produces the amount of cash needed.My point is that your own goals and needs should dictate your investment strategy and determine the metrics you use to acquire your rental portfolio.   

It's probably much more complex than you need and a Promissory Note and potentially a mortgage (if they are lending for a particular property rather than to your entity) would suffice.

I understand that future capital improvements would be depreciable but if none of the value of the existing infrastructure can be applied towards the basis, it obviously reduces my after-tax returns.If the answer to question above is no, can I effectively create a defensible basis by getting a cost segregation done that breaks out the true value of the infrastructure or, would the appraisal suffice since the appraiser would presumably provide a breakout of the infrastructure value?