Richard Osman confirms the TM house is still being rented out.

This is to put down any confusion I seen in this sub on whether the TM house is being rented to Avalon or Avalon bought it.

https://www.youtube.com/watch?v=-IFpT-j2R4A

Starts from around 15:57.

tl:dr London rental prices is still cheaper than buying it out.