[giantg2]

One scenario they're good for is if you own the land and need something to save up for a few years when planning/building your house. Although with the advances in modular and tiny houses, they don't seem to be the best option for that anymore either.

[bombcar]

They can work in some cases, but they should almost always be considered temporary housing (as they quickly cost more to maintain than they’re worth).

Of course some modular homes that have a technical mobile part are a different story.

Around here the “live while building” is usually done with a garage with a small apartment above it.