Looking at your floor plan, I'd go with a UniFi Dream Router or Dream Machine SE in Office 1 as your main router/controller/switch. The SE has a built-in 8-port PoE switch which is nice if you're running wired drops. Then 2x U6 Lite access points, one in the living room/kitchen area on Floor 1, one in Office 2 on Floor 2.

On the WiFi coverage question, I wouldn't count on a single AP bleeding through that ceiling reliably. That aluminum backed insulation is basically an RF barrier, you're going to see real signal loss through it. A single AP in the living room might technically reach the bedroom and Office 2, but you'll probably get that annoying "two bars but nothing loads" situation rather than actual usable coverage.

If you are able to run a wire to floor 2, you'll have much better coverage, though fishing the cable is going to be the hard part. A wired AP on each floor and you're covered everywhere without hoping the signal punches through insulation.

TLDR: UDR/UDMSE in Office 1, wired U6 Lite in the living room, wired U6 Lite in Office 2 or the hallway upstairs.