Can members comment on Maximum distance they have achieved using HE with Zigbee Door /Window contacts

Hi. Appreciate your post on the additional hubs. I have a similar question. Im setting up some humidity sensors at work to monitor the humidity in electronics labs. it's a large shop and i didn't think there is any way one central hub location will cover it. For the most part, i will have network access in every lab. My initial thought was to put zwave/zigbee repeaters around the building ( loving the centralite 3210l smart plugs) but maybe the additional hubs will be a more stable option. To that point....if i did want to go say 500 feet distance would 5 repeaters be stable?
2nd question please. If i use additional hubs...do those also act as repeaters in addition to a direct link to which ever device i connect to it?
Presuming on using zigbee humidity sensors.
Thanks in advance.
Mac