I want to set up a wordpress site and somehow use subdomains with it. I've looked at the Wordpress multi-site options but i don't think it does what I want. I don't want to have to change themes or plugins for everything.

I want one site with one theme and it to work like a standard wordpress install but instead of...

reviewsite.com/audi
reviewsite.com/bmw

it is

audi.reviewsite.com
bmw.reviewsite.com

So I can have one sitemap, etc.

Possible?

Anyone?

It's not possible to install using a single install. However, if you have Hostgator or any other big host, you can set up Wordpress pretty quickly, and then modify the theme just in one subdomain and copy it to the folders (through FTP) to all the other domains. Or simply modify the theme by Ctrl + C and Ctrl + V directly in admin.

FTP is faster, obviously

I think in WP hosting facility you may add ur subdomain; but what I guess multi site option is for multiple WP site; However, am not so sure. I think you better just to try to add a physical sub domain there for learning it practically.

How about redirects?

try redirects , it will work for you

if your hosting has a cpanel, login to cpanel, look for add subdomain, enter audi.reviewsite.com as your subdomain. After that look for fantastico or an application in your cpanel where in you can install wordpress. Then install wordpress on that subdomain.

make sure not to select your main domain when installing wordpress

hope this help