form landing page trigger

That's kind of a broad front-end development question!

If by "display" you mean "render in a DIV that's on the same page," then create a single function that you pass a form ID.  Then each button calls that function with a different value, for example:

<button class="formLauncher" data-form-id='389'>JOIN US NOW</button>

<button class="formLauncher" data-form-id='402'>GET A QUOTE</button>

<script>

for ( var formLaunchers = document.querySelectorAll('.formLauncher'), i=0, imax=formLaunchers.length; i<imax; i++ ) {

     formLaunchers[i].onclick = function(e){

          MktoForms2.loadForm("//app-aba.marketo.com", "XXX-XXX-XXX", this.getAttribute('data-form-id'), function (form){

               MktoForms2.lightbox(form).show();

          });

     });

}

</script>

(Note: I just typed this code into the comment box from my mobile, so it may have errors but you'll get the gist, hopefully.)

One thing you could do is use the form's Lightbox embed code, which you can find by going to the Form in Marketo, then clicking Form Actions > Embed Code and use the "Lightbox" version. For the buttons, you could make them link to part of that code. For example, if the embed code was:

<script src="//app-aba.marketo.com/js/forms2/js/forms2.min.js"></script>

<form id="mktoForm_9999"></form>

<script>MktoForms2.loadForm("//app-aba.marketo.com", "XXX-XXX-XXX", 9999, function (form){MktoForms2.lightbox(form).show();});</script>

Add the beginning two lines (which define the form) anywhere in the body of your page. You may want to add a string variable to the top of your template so that you can add these lines within the Guided landing page editor. You'd then call the MktoForms2.loadForm() function whenever you wanted the form to display.

As it looks like you're using a guided landing page template from our library, those buttons are declared in the template as something like:

<a href="${buttonLink}"><button class="btn btn-lg btn-trans">${buttonLabel}</button></a>

So, to avoid having to make any more changes to the template (apart from adding one string variable in the body for the first two lines of the embed code), you could add line 3 of the embed code as the button's link from within the editor:

javascript:MktoForms2.loadForm("//app-aba.marketo.com", "XXX-XXX-XXX", 9999, function (form){MktoForms2.lightbox(form).show();});