There is Class TextFinder in Spreadsheet service for Google Apps Script. Ref The TextFinder can search and replace the texts in the Spreadsheet using Google Apps Script. There is the method for createTextFinder in Class Spreadsheet, Class Sheet and Class Range. When these methods are used, you can search and replace the texts for all sheets in a Spreadsheet, the specific sheet, and the specific range in the specific sheet.
In this post, I would like to introduce the sample scripts for taking advantage of TextFinder.
I think that TextFinder is the strong method for searching values in Google Spreadsheet. Ref So I think that when this can be taken advantage of, the process cost of the script will become low.