Fix Excel Power Query Scraper

My workbook already asks SerpApi for HomeDepot.com data the moment I type a model number in the “Model” sheet, and Power Query pushes the results into the “Result” sheet. Two nagging issues stop it from being production-ready:

1. The cache sheet that should store the API response has stopped working, so every look-up now triggers a new, slow call instead of re-using the last fetch.
2. On the “Result” sheet the sale price reaches the correct cell, but the regular (full) price column stays empty.

I need someone who understands Power Query, Excel data model, and REST/API connections (SerpApi in particular) to:

• Diagnose and restore the caching logic so the workbook re-uses previously fetched JSON.
• Update the query/transform steps so the full price field is extracted alongside the sale price for every product tested.
• Hand back a clean workbook with the fixes documented briefly inside a hidden “ReadMe” tab, plus two or three sample model numbers showing both prices populate correctly.

No other columns are required right now, just sale and full price working side-by-side. If a small bit of VBA or an alternate connector is the easiest route, I’m open to it as long as the user experience remains a single model-number entry that auto-refreshes.