Given that it is a multi-family property and is subject to Los Angeles rent control laws, any rehab work is only beneficial if units can be delivered vacant or constructed after 1978.  

Especially coming from the perspective of RE as the primary driver of reaching FI. 

Not an expert on how to deny renters, but I've had to deliver bad news in business plenty of times.

I know jobs are a huge driver for the stability of multifamily properties.

I am looking for some advice on how to form this letter, and the best ways to deliver it - Certified Mail is what I was considering. 

We need either their SSN and/or their drivers license number to perform the national database search. 

It's what everyone sees and remembers.A good rehab designer will know where to spend money to get the most bang for your renovation buck, how to deliver everything from curb appeal to intimate interior details, with taste and the proper respect for the existing arrchitecture.

I recently borrowed 50k of my own money from 401k which was delivered in a check to mail box in less than 5 days for a down payment .

In the purchase contract, it states that if the seller does not deliver marketable title he will refund the earnest money to me, the buyer.

You would think they could operate a screw driver.