Here's what to do.
1) Place the order.
2) Once the order is confirmed ring BT and ask them to check with OR if the installation will be a 2 stage or 1 stage installation.
3) if it's a 1 stage then you can turn the installation appointment into a de facto survey by simply asking the engineer what they plan to do, and then asking them to go away until you have spoken to your landlord. This will not be a problem for you, not will there be any cost to you. You will then have 14 days in which to rebook an appointment. If you don't the order will be cancelled by OR. But you could just place another order if that happens.
4) if it is a 2 stage installation it will be a trickier proposition. Usually OR will send an engineer to do stage 1 without notifying you as they don't usually require access to the interior of the property. But if you ask BT to speak to OR they ought to cooperate and tell you when the stage 1 visit will be. However if this goes wrong an engineer may well turn up and attach a cable a property to the property.
5) At the end of the day the landlord would be silly if they didn't allow this to go ahead. It would be like refusing to let the gas or energy companies to connect their services to property. The landlord will find it very hard to rent out a property that isn't connected to the internet
