For starters, why is 500 m not sufficient (what do you intend to do) ?
Going beyond 300-400 m altitude will make your drone BVLOS. So when you have figured out how to do this legally,
500m limit is 500 meters above its starting point, so climb the highest mountain in the region and takeoff from that.
Notice the drone will drain batteries quickly getting at this altitude and windspeeds can be much higher up there than at the takeoff site.
Also notice (light) aircraft & helicopters in the neighbourhood will also be using these altitudes and don't expect drones there.
The picture is of the Thörsmörk valley in Iceland @ about 500m altitude, on the right the Eyjafjallajökull volcano (1666 meters high) which erupted in 2010, causing all airtraffic Europe - America to stay on the ground. For me, this max. altitude is sufficient, also when you take windspeeds into account (timelapse @
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