What is the best practice for changes in task order, dates and predecessors?

I work for a residential construction remodeling company and one of the things I use smart sheets for is keeping track of the jobs progress. Before we start a job I set durations and a predecessors for the tasks that will be involved in the project. The problems I am having are the order of the project will change and the amount of time that it takes to do each task will change from my initial projections. Any suggestions for best practice on how to address the changing of the length of time a task will take and the order changing? Not sure how to indicate it because we would like to have a clear view of what we projected the dates and time to be versus the actual.

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