I am very new to GIS, so don't know if this is EXTREMELY easy or impossible.
I have GPS coordinates for stores (about 15000) for which I have created a buffer zone around each store location obviously (or not) in a single layer. In metropolitan areas I now have overlapping buffer areas. I would like to calculate the area where buffers overlap.
I have established how to do this if each point were a separate layer, but with 15000 points, I just do not have the time or the energy to do this.
I am working in QGIS.