Need Script that will change Wordpress Template Logo Link to a Different URL

Hello, My site is: www.housebuyersanantonio.com. I DO NOT have access to the Wordpress Admin area, because I use a company that manages the backend. I am allowed to add scripts to the head or footer, but not actual wordpress theme files. Here's what I need asap: 1) I need the logo link on all pages, to be changed via a script, from: [login to view URL] to: http://housebuyersanantonio.com. Please note that I don't want to change the pages to that url, just the a href link that the logo points to. It needs to be a working solution....you will generate the code and I will paste it into the header area...then, IF it works as I need it to work, I will release milestone.