anyway you can create air flow in the basement,, one side in and one side out within a basement window.. this would sure help.. even a fan on the floor could help move the air. self draining dehumidifier is great except they run constantly and is big electric usage.. another thing is to wrap cold water pipes so condensation is kept under control so it doesn't drip.. 

I'm switching the recessed lighting to LEDs using conversion kits to stop airflow to the attic before insulating it.

Tomorrow will be a quick check on the moisture, punch a few holes in the drywall to circulate air flow and change the locks.

We are going to try and add a damper to restrict   the airflow to those ducts.  

The biggest issues related to fridges are that the ice maker dies for whatever reason or the tenant leaves the refrigerator door open too long which results in the freezer over freezing and no cold air getting the the fridge as a result of build up in the freezer preventing proper air flow.

Thank you all for the reply’s I am going to use a pest control company to come seal every up from pests without restricting the airflow.

I'm not sure how long the electrical tape will hold, but that did stop the airflow when you place your hand over the outlet.

Sometimes these vents get closed and there is no airflow to carry away the moisture.

The trick was that as heat rises, the wall cavity was clear, and air flowed up it and out the vented attic.

If not, during the winter, your office space will be extremely cold because the air flow in your building will go from the ground and up to the top of the structure.