How large an area can an Inspire/P3 map?

The wind speeds should be about an average of 4.5 m/s at that height (82 m AGL) I’m going to be flying it at. Dronedeploy tells me the total flight time is about 138 minutes for the flight I’ve planned from the dashboard. So, assuming 15 minutes of flight per battery, that’s about 10 batteries. I have 3 batteries, so I’m looking to fly 3 batteries at a time with 2 to 3 charging breaks in between.

Yes, I’m concerned about the gsd variation as well, but I’m not quite sure how to take care of that. Any suggestions? The estate owner’s main requirements are to mark his boundaries on a map and measure total area, measure the productive growing area of his plantation, and measure areas of various features like water tanks and roads in his estate. Would the gsd variations (altitudes would range 82 - 332 meters) come in the way of doing these measurements accurately?