I'm very interested to see what you put together for your network gear!
I'm a ubiquiti fan as well, sounds like you are going for an impressive setup.
Here's the rundown on the hardware and general layout. My land has fiber running to the house, so we'll have Xfinity out there shortly to connect things up. I'll use their gateway device but disable as much as possible from the console (wifi, etc).
That will connect up to a Dream Machine Pro as my Ubiquiti cloud gateway. I'll run the Unifi IDS/IPS security configs along with a number of VLANS (Guest, IoT, Cams, etc). I'll use SFP+ to connect the UDM to a Pro HD 24 PoE switch at 10G. I have Cat6 wiring around the house, with those terminating to a 24 port keystone patch panel. This switch will support up to 2.5 GbE to each line along with PoE++. Plenty of room to grow.
I'll have 5 U7 Pro XG access points around the house (3 on the main floor, one in the basement, 1 in the workshop)...I was planning for U7 Pro but the XG just came out and was only $10 more each. The big difference with the XG is it supports a 10G uplink vs the U7 Pro is only 2.5GbE. I'll also use their G4 Doorbell Pro (who's ringing my door anyways?) along with other cameras keeping a lookout around outside of the house. The UDM will serve up NVR storage with an 8TB drive in it. That should hold 30 days of video.
I plan to run a fiber line from the Pro HD 24 switch in the utility room out to the workshop, where I'll have a Flex 2.5G PoE to handle switching and power for the wifi and cameras on that building. My subcontractor doesn't like the idea of running Cat6E outside in the ground - worried about lightning strikes? He suggested fiber would be about the same cost wise. Inside the shop and the daily garage I'll have either a dome or turret style camera on the ceiling at the back facing the garage doors. In the shop the only real data needs I have are for the cameras, so I likely could have put an access point in mesh mode and been ok. But since I'm building from scratch...
All in it is about $4K in Ubiquiti camera and network gear which in the grand scheme of things feels like a rounding error.
Ubiquiti has soon cool design tools that I used to spec some of this out, simulating wifi strength, camera coverage, etc. When I get home tonight I'll try to remember to take some screenshots and add them for those not familiar with it.
I could clearly go on forever. Some people would just throw eero or netgear stuff in and be done with it. And it might work great for them. It is in my nature to tinker with this stuff. I also have a Home Assistant running at my current house - plan to do the same on this house to integrate and manage all my tech.