you contacted mobile provider to ask why in leeds they cannot provide a decent indoor signal? That to me is bizzare.
Also have you tested different mobile provider signals (even with PAYG)?
If 4g works, now days i think its a viable backup.
There is only one provider that can provide a service good for voice calls at this property, Vodafone. No-one can deliver data to the ground or first floor. This has been tried out with O2, Vodafone, Three and EE.
We are in a slight depression in the ground and are surrounded by houses. There is a 1.8 metre criblock wall on one side of us.
Intermittent data service is available on the second floor if phone is placed on windowsill.