6 unit with single zone heating

[Dan McCarthy]

Recently purchased a 6 unit building that has one central oil boiler that provides shared heat for all units with one zone. A friend had mentioned installing a thermostat by Honeywell that has 4 - 6 sensors that report back to the thermostat to then try and average the units and come up with the appropriate thermostat setting to keep all units where they should be. Has anyone heard of this or can recommend a better solution for this short term? Long term we are looking at possibly going with mini-splits on each unit to be able to pass the utility to the tenants and also provide A/C. Thanks in advance for the help!