Can anyone recommend Combined Utilities providers?

Other

I visited the recent London Landlord's event at Olympia, and one of the stands of interest offered a combined utility service, to landlords and tenants. I have heard of another company who did this, but cannot remember their name.

The idea is that you as Landlord sign up all the relevant properties with them, and then get only one bill (to cover all those properties).

In the Tenants' version of the service, each sharer gets their own bill, with a flat amount to pay each month (estimated based on number sharing and location), with an adjustment at the end of their tenancy.

You can select which of the following services is to be included: electricity, gas, water, landline, broadband and TV license.

We all know how agonising it is to switch utility suppliers, so I am nervous about putting everything in their hands - if it all goes horribly wrong then I am even worse off than before when I go to clean up the mess. That's why I'd like to see if other members have done this before.

Can anyone out there recommend such a supplier? What are the thing sot look out for when signing up with them?

Many thanks!