I'm thinking about using the Direct Mail Strategy to target multi-family properties and owners who might be motivated to sell. 

You should be mailing them, calling them, and possibly texting as well. 

Motivation!

If you’re less than 10 units, text works well, unless your properties have a lot of deferred maintenance.

By grooming these relationships, I keep a pulse on my market and my best deal to date came from a text from one of my Realtors saying "you're going to love me for this deal" and you know what, she was right!

We are putting in tons of extra hours contacting tenants via phone, text and email. 

I have been communicating with the tenant via text message, and certified mail because he would not provide an email.

 I would like to know, is there a phone script either through/on bigger pockets, online, or somewhere you can suggest, that I can use to negotiate a deal with a motivated seller to be able to get a contract if so I'd appreciate it thanks?

What's known is that Miami market is doing well and if a seller needs to sell (yes, people are still experiencing life events motivating them to sell), a buyer can do well right now with much less competition and inexpensive credit.

If they are motivated I'd still think they're worth dealing with these types of issues.