Multiple blogs on single site

Hi All,

We’d like to host 3, possibly 4, blogs on our site which would be located in different subdomains and directories.

The experience we have, so far, with WordPress is a single installation which goes in a specific directory. The admin etc. is also in that directory.

In this case, though, we’re looking at several blogs in different locations and we really don’t want to have to repeat ourselves with regards to things like plugin installation and upgrade, core WordPress upgrade etc.

1. What is the way forward?
2. Must it be that the admin section be in the same folder as the blog itself?

Thanks