453589 SEO Urls for Oscommerce website

I have oscommerce website and the seo urls are giving me many problems. The site has been customized and seo urls creates errors on many page because it doesnt seem to be configured in the best possible way. I will need you to examin it carefully and fix. If you do not have any experience with this type of thing, please do not bid. 1.I would like it configured so none of the pages create errors [login to view URL] default the pages should take there names from current category [login to view URL] that contain products should take there name from product name and model number. Both model number and product name should be in the url 4.I will also like the ability to customize urls for certain pages, controlled from admin, for seo purposes 5. Links in drop down menu need to also be configured to have seo urls without causing any errors 6. Items per page: 20 | 40 | 100 | 200 should have seo urls also without causing errors