The MHRA have a guidance checklist for such use:
https://assets.publishing.service.g...data/file/403401/Devices_in_practice.pdfYou can worry less about the electrical installation in the home if the devices you send are class II (double insulated)!
In some rural locations only a TT supply is available, which will mean the electrical installation is protected by an RCD.
Maybe include a reminder that an electrical installation condition report (EICR) is recommended every 10-years and is mandatory every 5-years in rental properties.