Well - they came on Thursday and were clearly very interested; then came back today with a surveyor friend. I can only wait and see. Luckily very sunny, so I was outside; and indoors they wore masks and I had all the windows and doors open, so they did not have to touch any door handles at all.
I then went round with the bleach, and left the house for a couple of hours to go for a walk - time for bugs to die.
Fingers crossed!
Only slight problem was that estate agent who rang me to arrange the appointment failed to tell the viewers. Unbelievable! Luckily I had the agent's mobile number and got hold of him and he was able to ring them. I thought the whole reason we pay estate agents a fortune is to arrange viewings!!!