What is the average size you scan? Portable ones are really handy, I agree. Never tried Einscan, I use Artec Space Spider and scan objects mostly 15/40 cm in diameter. The results are really fine. It's specs are a bit better then Einscan, but If they suits your needs I think that would be a good cho...

Well, I've found a tutorial for an assembly drawing. It's for 2018 version, but i hope it helps.