In this day and age, I would expect to be able to control my settings for the entry phone online. £35 would be a reasonable charge to set up a new online account with the provider – after that a user should be able to login and make as many changes as he or she wants. So if you were away from your flat for a few weeks, you could change your contact number accordingly. This isn’t advanced technology by any means – we’ve all been able to divert calls to our mobiles for decades!
Diane – this should mean that new residents would still need to pay the charge, but existing residents would not have to pay it multiple times.
The OP is a director – perhaps he could look into who the £35 charge goes to? Is it the amount charged by Anchor Doors, or is some or all of it a ‘handling’ fee charged by Principia?