I am currently testing out these...

https://www.ubnt.com/unifi/unifi-ap/

They do "zero hand off" roaming.

I don't think that model will work for you as stupidly it runs at 24v not 48v.

I read reviews of these things and thought it would help out with slow WiFi in parts of my house. We have a small house but it's 3 levels and there doesn't appear to be one spot that works well for all 3 levels. So far I'm less than impressed. The throughput from them is okish sometimes but mostly poor, and WiFi access seems to lock up sometimes. I haven't decided if I'm keeping them yet. Unlikely at this point.

Cheers

Cris