Wordpress Installs on Business Plan Acct

OK, just opened a new Business plan and will be migrating 4 domains. I will be rebuilding each site as a Wordpress site. I'm a newbie with Wordpress (as this next question will probably indicate :p), but there shouldn't be a problem adding the additional 3 domains as addons and installing a Wordpress instance in each domain, right?

Oh, and in this case, should I create the Wordpress install on the primary domain within a subfolder?

Thanks!
tbone