I've always found that youtube.com is a good source. I have used meshes since day 1 (6.0) to model terrain / roads / sites from various sources (surveyor xyz, raw GPS, & guestimating) and have found it is still the best way for doing siteworks. I tried Architerra for a number of years but always found myself reverting back to simple meshes to get the jobs done.
This series of terrian modelling by Ioannis Spyridi has taught this old dog a few tricks. It is well worth the time spent watching these videos.
https://www.youtube.com/user/ispyridis/videos
Let me know how it works out.
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