Reverse charge on Security services  and Rent

Hi,
We are in receipt of security services from a GST registered individual supplier. They are not charging GST since january, 2019. Do we require to book GST on the same under RCM and take credit at the time of filng of return.
Second the same scenario in case of rent to an GST unregistered individual for commercial premises. Whether we have to book GST under RCM and take credit of the same.

What will be the Revers.e charge on Security services  and Rent.