I tried in this way:
Point LocXY = this.Location;
MessageBox.Show("Top left corner location: " + LocXY.X + "," + LocXY.Y);
MessageBox.Show("Bottom Right corner location: " + (LocXY.X + this.Width) + "," + (LocXY.Y + this.Height));
MessageBox.Show("Bottom left corner location: " + LocXY.X + "," + (LocXY.Y + this.Height));
MessageBox.Show("Top right corner location: " + (LocXY.X + this.Width) + "," + LocXY.Y);
These message boxes are annoying but you can use the result in the way you like.
Hope it helped.