function checkInput(f) {
	var hasError = false;
	var error = 'The following problems were encountered:\n\n';

	if (trim(f.quoteFirstName.value) == '' || trim(f.quoteFirstName.value) == 'First Name') {
		hasError = true;
		error += 'Please provide your first name.\n';
	}

	if (trim(f.quoteLastName.value) == '' || trim(f.quoteLastName.value) == 'Last Name') {
		hasError = true;
		error += 'Please provide your last name.\n';
	}

	if (trim(f.quoteCompany.value) == '' || trim(f.quoteCompany.value) == 'Business Name') {
		hasError = true;
		error += 'Please provide your business name.\n';
	}

	if (trim(f.quoteEmail.value) == '' || trim(f.quoteEmail.value) == 'Contact\'s Email Address') {
		hasError = true;
		error += 'Please provide your email.\n';
	}

	if ((f.npa.value + f.nxx.value + f.xxxx.value).replace(/[^0-9]/g, '').length != 10) {
		hasError = true;
		error += 'The installation phone number does not appear to be valid.\n';
	}

	if (hasError) alert(error);
	return !hasError;

}

function trim(s) {
	return s.replace(/^\s*|\s*$/g, '');
}