Creating a Simple stand alone Search and Replace Utility

Creating a stand alone Simple Search and Replace Utility I want a simple utility building to allow me to find and replace blocks of text elements within a html document that has been copied into it. The utility will allow me to use highlighter colors to individually mark each section for replacement and the utility will find and replace each section in order defined by the colors. Html coding will be left in place only text will change as required. Utility will have "Keyword" function that replaces all the keywords designated by a specific highlighter color and a Body Text Function that will change the text designated again by a specific [login to view URL] will ignore any code or text left not highlighted. Should have select all copy all facility to allow me to copy/paste back into a WP template. Should be a walk in the park for anyone experienced in this type of work. please no generic bids and I do know how simple this is so keep the price sensible please.