PHP errors when installing template on joomla 3

Hello my name is Alex. I manage the site potentialproject.com which uses the hot cars template. We are upgrading to joomla 3 and have purchased the latest version of the template. However when it is installed I get the following error.

Strict Standards: Non-static method JApplicationSite::getMenu() should not be called statically, assuming $this from incompatible context in /var/www/vhosts/potentialproject.com/httpdocs/mmp_upgrade/templates/hot_cars/index.php on line 40 Strict Standards: Non-static method JApplicationCms::getMenu() should not be called statically, assuming $this from incompatible context in /var/www/vhosts/potentialproject.com/httpdocs/mmp_upgrade/libraries/cms/application/site.php on line 279 Strict Standards: Only variables should be assigned by reference in /var/www/vhosts/potentialproject.com/httpdocs/mmp_upgrade/templates/hot_cars/index.php on line 40

As well in the backend of joomla when trying to access the template i receive this error message:

Catchable fatal error: Object of class JDocumentHTML could not be converted to string in /var/www/vhosts/potentialproject.com/httpdocs/mmp_upgrade/templates/hot_cars/elements/loader.php on line 40

Any possible fixes for this? Thanks you

Open:

templates/hot_cars/elements/loader.php

replace:

$header_media = $document->addStyleSheet(JURI::root(1) . '/templates/hot_cars/css/admin.css');
$header_media .= $document->addScript(JURI::root(1) . '/templates/hot_cars/js/jscolor.js');
with

$document->addStyleSheet(JURI::root(1) . '/templates/hot_cars/css/admin.css');
$document->addScript(JURI::root(1) . '/templates/hot_cars/js/jscolor.js');

Go to joomla global configuration and level down "Error Reporting" parameter