Editing developed website, design & few upgrades (already fully ready n responsive design)

We have a fully developed template and an website which is installed on whmcs, all pages r ready including 100% design, and the design is fully responsive .. we want to make minor changes to it, like adding some features (using the same template design as its fully developed n coded), like adding some new text or copying the graphic like if its one server table with graphics u can copy it to create table's .. having same graphic in that page, mostly you would just need to copy and paste it as its a fully developed website .. We want an experienced developer who can keep the primary code same, as its a fully responsive and high quality coded website .. so it should remain same while making some edits to it, you would also need to make few minor new changes to the overall website keeping its theme same, you might also need to add up some new text there, however most of it is already written n ready .. We would also want you to change the logo of it, n develop a new one using the same color scheme its just one image, which can be replaced n will start displaying at the header of our website .. rest things will remain same .. might need to make new images, like our payment processor company logo n add it to our template .. So its a fully developed website which we need to edit up, change the logo (create a new image), some design work .. but you should be highly experienced with responsive web development, HTML 5 n PHP, as you should keep the code same n only use few minor changes to it, n do not ruin its responsiveness .. might need to add some extra text to it too ..