Backyard coverage

Looking to add some wifi coverage to my backyard. Furtherest distance is about 300ft from where id mount an AP straight, then probably 50-75ft to the sides. All pretty much open space - just a couple trees but nearly clear space off the back of the house.

Based on cost I was looking at the Swiss army, but wondering if that will do the job. Only a few devices - couple cameras, bird cameras, and irrigation timers and an occasional cellphone.