UK Visitor & 'right-to-rent'

[konewone]

My girlfriend from Vietnam is applying for a Visitor Visa to come to the UK for 3 months or 6 months. I will sponsor her for living expenses and accomodation.

There is a hurdle getting the landlord's permission for her to stay. The rental agency wants to see her visa before they give her permission to stay. Of course that's not possible, because UKVI needs such permission before they will grant any visa! Assuming that the agency is considering the 'right-to-rent' policy, it doesn't apply in this case because she is a tourist (so it is not her first home), but they can't know she's a tourist without seeing her visa. This whole policy seems to have made it impossible for any visa national to get a visitor visa.

Two questions:
1) What options do we have for getting landlord's permission? Is there any way around, or is this policy just a way of saying that visa nationals are not welcome?
2) What is the latest timeline for roll-out of right-to-rent? I heard it was to be rolled out in July, but the website still only mentions Birmingham/Wolverhampton etc.

[Wanderer]

Might need to be careful with this one - it looks to even me this is more like residing rather than a genuine visit.