Getting ready to build a shop- first time in many decades I have done so- perusing this forum for ideas.

RustyRatRod said
All I can offer is, figure out how big you want, then double it.

What R3 said.

Best to build a little work party space where you can hang out with your buddies. Keep the rest out of sight locked. Make sure everyone understands you have no space to store others stuff ( including your wife/girlfriend).

Wish I could follow my own advice.