Added sensors and changed out registers throughout the house. Soent time walking thru the house looking in all the rooms and the units on the roof getting an idea of how best to even out the airflow. Sensirs were added to the rooms with lowest airflow and a game plan was discussed with the owners. Due to the amount of rooms and given it will have different people staying finding a certain temperature is unlikely but we may have a chance of getting a range of temperatures which will help with the start n stop of the unit. All 3 thermostats were acting as one and none of them are in ideal spots to judge Temps. Feedback on changes is required to help find us determine how to set airflow and more sensors will be needed to better get an overall average temperature to go off of. Without access to the ductwork and given they have no dampers in the rooms the current setup as it stands is just a start and by no means solved the issue. I've told the customer to remain in contact with me and I'll