I will install WORDPRESS Multisite/Network in shortest Time Possible for $5
|WordPress Multisite network makes multiple site management easy with single WordPress installation, also save lots of time and Resource. No need to go with separate WP install for each site.
*** instead of installing 2 or 3 wordpress for you subdomains, you can just install one on your main domain and the subdomains will share the same plugin and theme. its awesome idea.