The answer is the coping needs to be done first since you need to attach your forms to the pool walls where the tile will go. This is also important since you need to measure all of your tile from the lowest point in the bottom of the coping to ensure that your tile lines are all even and can be installed without cutting.
I hope this information is helpful.
Steve Goodale
Serendipity Pools & Artificial Rock
Swimming Pool Repair Online Resource Artificial Rock - Instructional guide and online store
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