An addendum here that architectural firms and builders will still often spec out MMF for in-building fiber. You want to tell them "No, use SMF instead". They w

An addendum here that architectural firms and builders will still often spec out MMF for in-building fiber. You want to tell them "No, use SMF instead". They will look at you funny and maybe even tell you "that's more expensive" because they haven't looked at price lists in over a decade. But they are wrong on all counts (unless you exist in a really whacky market). The only exception here is that some video, HVAC, etc systems require MMF to stay in warranty. In those cases, run both and use the MMF only for that junk.