My bank & others locally not interested due to property being classified as non warrantable.

I knew this going in - but because this is non-warrantable (due to OO ratios), it makes financing difficult - not just for you, but also whenever you decide to sell. 

Forms can be misleading - - we THINK we understand what to do, we all can read, B U T sometimes there are consequences we didn't understand.The QC or Warrant Deed is trivial - - The PCOR (prelim Change of Owner) is where the rubber hits the road and you hit with sales taxes and other consequences.Why gamble? 

If your financial position warranted it and the property has equity you could do a cash out refinance of it to get investing capital. 

If I am doing nothing but loaning money, I generally expect nothing but interest, maybe with a position on the note if warranted.

Worcester is close enough to Boston with a low enough entry price to warrant looking at in your case.

Do I need to send out a letter to the tenants letting them know I have proceeded to issue a warrant for removal?  

DRAIN STOPPAGES.As of the date of this Agreement, Landlord warrants that the dwelling’s sewage drains are in good working order and that they will accept the normal household waste for which they were designed.

Special Warranty will only warrant the deed for a certain time period, so there may be gaps in the chain of title.

Then you're likely needing to find a lender that does "non warrantable condo" financing.