Advanced Taxonomy Queries WordPress

I am working with wordpress and business listings. I have about 5000 business listing all over the usa. Each business listing has a custom field for state, county and city and brands.

My business listings are car dealers and each dealer is loaded into my wordpress database under a custom post type called dealers.

I have created two taxonomies called geography (logical structure = states ->county->city) and brands (ie. Honda, Toyota) to be able to view dealers by different queries options.
It is my understanding I can query between the geography and brands taxonomy with parameters and it appears to be working.

For instance, www.xyz.com/dealers/?geography=alabama&brands=toyota. This query would list a category page of all dealers in my database in the state of Alabama with a brand of Toyota.

I now need to create dynamic category pages for hundreds of different query options by geography and brands. Here are the options:

1. All dealers by each state in the USA
2. All dealers by each county in USA
3. All dealers by each city in USA
4. All dealers by each brand
5. All dealers by each brand and state in the USA
6. All dealers by each brand and county in USA
7. All dealers by each brand and city in USA

I assume I can have a programmer create a category template in wordpress for each of the above option and rewrite the urls to friendly to query the various options in my db.

Can someone provide me some guidance if the above approach appears wise or is there a better approach that would be more efficient? My concern is the above approach might not work and also I spend a lot on programming and then a future release of wordpress changing the permalink structure and my solution does not work anymore.

Your assistance is very much appreciated.