And that us not what OPmasked.
Yes, we did a viewing on Sunday. We had all internal doors open and all lights switched on. We then simply stayed downstairs when they went up, and went into different rooms on the ground floor. Close enough to answer queries, and keep an eye on them, but much more than 2m apart.
We disinfected door handles etc before they arrived, but they actually made a point of keeping their hands in their pockets.
It was no problem, except there was no small talk, it was all very brief.