for this you`ll have to edit composite_property_details.html and delete this:
<patTemplate:tmpl name="roomslist" type="simpleCondition" requiredVars="rooms_list_title">
<div class="htitle">
<h3>{ROOMS_LIST_TITLE}</h3>
</div>
{ROOMS_LIST}
</patTemplate:tmpl>
and add this somewhere below (after the availability tab for example)
<patTemplate:tmpl name="roomslist" type="simpleCondition" requiredVars="rooms_list_title">
<div class="tabbertab">
<div class="tab_panel_content">
<h3>{ROOMS_LIST_TITLE}</h3>
{ROOMS_LIST}
</div>
</div>
</patTemplate:tmpl>