Or is WordPress fairly small in size?

Hello,

We are going to redesign our website Covoco. What we would like to do is create a multi-site network. Currently we do not use multi-site and the site has gotten too big. We have 3 distinct users that would benefit from having their own site. Is it better to have 3 different installs or use a multi-site. I’m worried about the space that different wordpress installs would create. Or is WordPress fairly small in size?

 

Any help will be appreciated.

Thank you.