Thank you for reaching out to us on the Microsoft Q&A forum.
After reviewing the formula you provided, we can confirm that the correct version for formatting the Machine Price in a currency format is Text(Value(ThisItem.'Machine Price'), "$ ##.00")
We have tested this on our end as well, and it functions as expected, accurately displaying the price with a dollar sign and two decimal places. For your reference, please see the attached screenshot confirming the results.
Please reach out to us if you have any other queries.
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