I have absolutely no experience in running a letting agency myself, however I am pretty sure if I were to be put in charge of Strawberry Lettings and told to be as incompetent as possible, I would still manage to provide better service than they can. Perhaps while sleeping at my desk I might get startled by a ringing telephone and accidentally knock it off the hook, thereby achieving the goal of answering the telephone.
Strawberry Lettings are a perfect example of how not to run a letting agency. Any issues brought up after checking an inventory are not seen as things which need fixing, they are just viewed as things to not try and charge you for at the end of your tenancy.
God forbid you ever have an issue where the landlord cannot be contacted - Strawberry seem to think it's acceptable to use this as an excuse to not get repairs carried out that require money to be spent. If their contracts with their landlords give them absolutely no comeback in a situation where a landlord is simply ignoring them then they are even worse at the legal game than the letting game.
To sum it up, they may advertise professional lets, but their service is anything but.