I'd put a NanoStation M5 on building three as an Access Point and have the radios at 1 and 2 be configured as stations connecting to it.  For as cheap as they are I'd go with Nanostation Loco AC radios.  I built a half mile link with a couple AC radios last month that is streaming 6 cameras across it.

As Lance said, I'd go with a Unifi access point, probably on building three as well to cover the yard.  Go with the Unifi AC Mesh radio as it is outdoor rated.  You'll also need to install the Unifi controller on a PC or Mac to configure it or purchase a Cloud Key.