Ajax / jquery form validation

This should be simple, but with my limited skills I'm finding this difficult. Validating a form with normally takes me 15 minutes, but not this time and I'm stuck. The search form is on the page [login to view URL] The 'Location' and 'Product category' fields are compulsory. Normally I can do this via ajax, but not this time because: 1) the Location field is in fact a Google Places autocomplete field, and whatever I do I can't get my validation script to recognize the field, even though it has a name tag (name=zipcode). I suspect that because this autocomplete is already using a jquery (1.11.1), this is causing a conflict. But I can't be sure. 2) the Product category checkboxes are populated from mysql. For some reason my script doesn't recognise the checkbox values (name=categories[]). if location and/or category are left blank, an error message has to appear to the right of the 'start search' button when it is clicked, for example: "Please complete the missing fields", and at the same time the words 'Location' and/or 'Product category' are highlighted in red. In the attached file, the <form> tag begins on line 237.