Extract value from iframe converting var content to text?

I’m trying to get the dollars value that is inside an iframe ($75.12). I can store the iframe doing this:

var frm = document.getElementsByTagName("iframe")[0]

but I cannot proceed doing something like

frm.contentWindow.document.getElementsByTagName("div")

since I get security error about cross origin frame.

Is there a way to store the content of variable frm in plain text? or what do you suggest?

The iframe looks like this:

<iframe class="transact-client-iframe transact-client-open" name="transact-client" src="https://examplesite.com">
'#document (https://examplesite.com)
<!DOCTYPE html>
<html lang="en-us">
    <head></head>
    <body class="transact__layout--flex">
        <div class="animated idx" style="display: none;"></div>
        <div id="ufst" class="vetyu-apptn">
            <div class="apptn">
            <div class="apptn_header"></div>
            <div class="apptn_content">
                <div class="py-values">
                    <div class="py-values_wallet">
                        <div class="py-values_balance">
                        <div id="vetyu6" class="help-popout vetyu-view"></div>
                        <div class="py-value">$75.12</div>
                        </div>
                    </div>
                    <div class="row align-center"></div>
                    <div class="py-values_ctas"></div>
                    <div class="py-values_preferences"></div>
                </div>
            </div>
            </div>
        </div>
        <form style="display: none"/></form>
    </body>
</html>
</iframe>