some time ago a m3ember asked about drawing a building in perspective. I suggested a 1 point ito keep things simplw, this was nit well received. a little while ago I ran across a youtube video that shows very well what I was referring to. Take this as you will. This video shoa freehand method of sketching in perspectove. While there are methods of keeping the various elements that are receding in the proper sizes assuming they are the same size to b4egin with. Never the less this is a very good video.

https://www.youtube.com/watch?v=FeUaC9cOjEg