Best Process to mass-mail rental agreements

MMSP_Acq

Hi All,

If needing to send a physical mail of rental agreements to each customer at a facility-does anyone have a best practice outside of using Simply Certified?  Everytime we try to process it needs a major change to the HTML code, and I just don't have access to someone who can make those major edits.

(Needing to do this due to new acquisition of property and don't have full tenant information such as email from previous management)