However, as your business grows, you can employ some great time-savers to leave you more time to sort through actual deals than dealing with mass-mailing replies all day.Reality Check! 

Generally speaking, he rants a lot about Taco Tuesday buyers (the uniformed masses, buying out of priced-out-forever panic), and then highlights the listing(s) showing how ridiculous (in his opinion) the market has gotten. 

So my company and I are getting ready to start a massive, year long, mailer campaign.What I want to ask the BP community is what mass mailing websites, sources, list websites, etc... do you recommend?

I don't know in mass but here in providence they also offer 100% financing which means no down payment at all.

I'm originally from Boston, Mass but been raised in Miami,FL.

Look at MASS Housing, that is what i am trying to do as a house hack. 

I own a mixed-use building (free and clear) in the downtown area of a rough city in Mass (2 efficiency apartments over a commercial unit).

Most of the newer homes are pop-up houses that were mass produced.  

The reason I ask is that I keep hearing how Landlords basically have little to no rights here in Mass. when trying to deal with a problematic tenant, especially if they have written lease.

Closest to you would be Eastern Mass REIA in Taunton (2nd meeting in Rockland).