Terrain extensions

I am a landscape designer, and pretty new to Sketchup. I have Sketchup Pro 14. The terrain modeling seems very complicated with Sketchup. I deal many times with sites that have slopes, and other undulating terrain, where we would like to show our clients patios, retaining walls, steps, etc. I need to show the existing topography, and I will shoot elevations. Please let me know if there is an easy way to model terrain, or, what you may have found that is an easy terrain extension that one may purchase, or that is free. Thank you.

You should have a look at TopoShaper.

You could also try this extension:

Best regards,

Landscape not my wheel house => electrical eng;
Have you look at downloading the terrain data from Google earth. You can get 1Kmx1KM section without stiching which is probably ok and you can then create contour data from that. Depending on which satellite the data is from it may be 50 cm resolution; US gov made agreement in June 2014 (?) to allow change to 25 cm but don’t know if that is available yet=> probably not with lead time.
Do you have lat / long of candidate test area you can post?

FYI You Tube info Importing Google Earth Terrain into Google Sketchup - YouTube