Classifieds Site Modifications

I have a classifieds script (mybizz classifieds) set up on a site. It works fine, but I want to make a few adjustments to it. 1 When the Ads are posted, the URL generated is not Search Engine Friendly, i need them to be. IE siteurl/date/ad_title (obvioulsly, all urls must be unique) 2 I need it to generate an xml sitemap automatically 3 I would like to add a couple of functions to the ADMIN ONLY, i want to be able to submit an Advert through the admin (you can do this at the moment) but have the option to assign the Advert to ANOTHER user rather than the Admin, eg, so i can upload multiple ads for other peoples accounts. It could be just a simple drop down box with the function to select other users names to assign it to them. I have one package for 1 photo, another for multiple photos. There are occasions when i want to upgrade and ad At present i can edit anyone's ads in when logged in as admin, but i can't upgrade them to a different package. This function is needed. Please put the word Mybizz in your bid, so i know you actually read this and are not bidding without reading the brief. 4 General site security check. Make sure site has defence from sql injections and other possible attacks ie flood. A small part of the code is encrypted but i have the [login to view URL] file needed to make it work. I won't escrow payment until you have looked at the job and are confident you can do it. All fairly straightforward if you know what you're doing. Please do not bid if you do not have experience in this field! More work for the right person.