Hi,
There is indeed no option to display the retail price on the listings of products.
So a code modification is necessary.
It's indeed the modification I recommend on that other thread that needs to be done.
Note however that the code is twice there:
monosnap.com/file/35bEvZy4a7mCBXYCC7TmgepqxZ54z8
Note also that the code changed and it's not anymore:
&& JRequest::getCmd('layout') == 'show' && $this->params->get('from_module','') == ''
but:
&& hikaInput::get()->getCmd('layout') == 'show' && $this->params->get('from_module','') == ''
that you need to remove so that it can display on the listings.