Q: Can I install windows 8.1 update 1 on a 30GB ssd I have a computer with an empty 30GB SSD, and no place for another drive. Can I place a usable Win 8.1 on this drive, or should I buy a bigger one?
I see in the comments that moving the Users folder is a bad idea. Can I fit everything I need into 30 GB?
Does Windows 10 take smaller place?

A: When you use the new WIMBoot feature, Windows doesn't requires a lot of space. This feature was added with the 8.1 Update to make sure Windows 8.1 also runs on Tablets with 16GB storage. So 30GB is enough to run it as WIMBoot.
Microsoft explained this here in detail:
Windows Image File Boot (WIMBoot) Overview
What is Windows Image Boot (WIMBoot)?
