The owner needs to give you two documents: P & L (profit and loss) for the past 12 months (the "trailing 12"), showing you all income coming in monthly, and all expenses per month.

That was standard, they wanted to see all your financial documentation, but I haven't used them yet so I am not sure how they are with closings.  

How loans should be:  Approve a loan with a specific buyer(s), seriously put them through all paces including tax transcripts, employer verification, account verifications for any downpayments, gifts, whatever they need for approving at their target price, all documents needed to give them total clearance for x amount for PI before they ever walk into a home looking to buy (with no change in income or debts, of course).  

Start with a blank document that is the same size as your postcard in Word/Publisher (4X6 or envelope etc).

I prepared a letter of explanation with the desired outcome of setting a call or meeting to discuss but before I send the letter out what other tips or documents should I enclose to showcase my legitimacy as a buyer and my seriousness specific to this property?

You have to use a disinterested 3rd party to the transaction to document and transfer funds from the sale to your exchange account and from your exchange account to the purchase which must also be documented and all along the way.

Hi All,I'm looking for a checklist kind of document that I can hand someone and have them walk every single unit in an apartment and check off a list of things. 

It's usually written into the loan documents that they have rights to the insurance proceeds or that they must be named as additional insured /loss payee etc.

and as far as legal docs go, shouldn't  there be some specific documentation to ensure the borrower doesn't run off with the money ?

I then provided them with all documentation and verification for my financials.