2 instances of HA for home and office

I have home assistant installed at home running various wifi and z2m devices . I also have an office located in the garden possibly 70-80 yards from my house where I have a wired access point to give me internet acces. I would like some z2m automations in the office and have a second unit that I can load HA on. Should I just build a second HA instance and wire it to my access point? I read somewhere that I cannot have 2 mosquitto brokers running on the same network so would I need to link the 2 HA instances? Many thanks for any responses.

I think it will be overkill, but you can try this integration

If you already have a wired access point, you could put a switch there, connect the access point and a ethernet Zigbee coordinator to said switch and install a second Z2M instance on the HA installation back at your house. That way you get one HA installation and Zigbee out in the office.

Many thanks, did'nt even think of running a poe coordinator on a second z2m.