Multiple Installations of WordPress

Hi,

I have used WordPress as a content management system. To do this I played around with the template, added custom category-2.php files and changed some of the wording. This allowed me to create a ‘review site’ where every category was a letter e.g. ‘a’, ‘b’, ‘c’. So for each letter all the games were listed!

I’m now taking on a much bigger project and wondering if I could create multiple wordpress installs on the same domain i.e.

https://www.domain.com/reviews/ <– wordpress in here
https://www.domain.com/interviews/ <– another wordpress install
https://www.domain.com/filedatabase/ <– another install

Is this feasible? And does anyone know if it would have any negative effects on SEO?