Hi @wiredupjax ,
I have made a test on my side to create a List 1 and List 2 as below:


The location column in the two lists with single line of text type, the count field in the List 2 with number type.
And multiple items in the List 1 would has only one corresponding item in the List2.
And then you could refer to screenshot below to create the flow:

The length expression in the count field as below:
length(body('Get_items_2')?['value'])
Best Regards,
Alice
Community Support Team _ Alice Zhang
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