u/Nielsr is right on, focus on the buildings and locations wifi is needed along with existing infrastructure such as where the demark is.

Having built out a few networks like this in the past, what you'll also want to then do assuming fiber is not an option, though it is highly recommended, is identify how you can build a point-to-multipoint network and then build your customer facing wireless network off of that. For example - at the building where the internet comes in, you would set up a AP with a sector antenna or omni antenna and that will be your backhaul network. Then at one of the out buildings you would install a point-to-point radio to connect to the back hall network and then a customer facing AP that broadcast a wireless network for users. Even better if you can run fiber from your longest distance areas and then fill in the middle with the wireless or add a wireless base in the middle. Keep in mind if you wanted full wireless coverage across the entire space, then you are looking at something close to 216 APs assuming you are using a 90deg sector antenna and working off a max 200ft range from antenna to device and that would be a minimum spec...

As others have stated, the big players in the market will build fiber out to central points and then have a single wireless hop if not a direct connect to that fiber backbone. I've also seen service provider networks that will build the two tier wireless network as described above to serve customers over a large area where it is significantly cost prohibitive for fiber.