Referencing data in JSON in Powershell via foreach

Question

I'm accessing some JSON data using Invoke-RestMethod and I want to iterate through it, performing another Invoke-RestMethod per id and using the apiHost value for each call. A simplified example of the data is below:

    "items": [
    {
        "id": "1234",
        "apiHost": "thishost.com"
    },
    {
        "id": "5678",
        "apiHost": "anotherhost.com"
    },

Here is the function as i have it so far. The Write-Host line (for troubleshooting this) displays ALL the apiHost values per id and explains why the next lines don't work. How do I refer to the relevant apiHost per iteration through the id so that the next lines will work?

function Get-ID  {$headers = @{
    'Authorization' = $auth_string
    'Org' = $organization
    }
    $response = Invoke-RestMethod -Method Get -Headers $headers -Uri $a_url
foreach($id in $response.items.id) {

    $itemheaders = @{
        'Authorization' = $auth_string
        'Dept-ID' = $id
        }

    write-host $response.items.apiHost

    $apihost = $response.items.apiHost + '/here/there'
    $outfile = 'c:\temp\' + $id + '_details.json'
 
    $response = Invoke-RestMethod -Method Get -Headers $itemheaders -Uri $apihost -outfile $outfile
    
    }
 }

This post seems to suggest what I'm doing is correct, but I think I'm missing something obvious.