LOL -- this is just some wannabee author, not James Bond.
Well, let me tell ya from the point of view of an investigative reporter , (retired)- who knows the tactics some will go to - when they are of this man's ilk - a muckraker hoping for a tid-bit, ANY tid-bit, one tiny phrase, one tiny action, to get himself a best seller.
By deliberately renting the house 15 ft from her backyard, he shows himself to be a bottom feeder.
And listening devices are available online to anyone, these days, cheap.
I "betcha" that EVERY one of you pooh-poohers who think Sarah is being paranoid or too sensitive would be screaming bloody murder if someone deliberately moved into your back yard with a view into your kids bedrooms - and you knew they were going to write a book about everything they saw and heard, your every activity, your comings and goings, etc - and that book would be published and read by hundreds of thousands - you'd sing a different tune.
And don't bother with "I wouldn't care 'cause I have nothing to hide." - You'd be incensed.
Add to that the fact that the person is hostile to you from the get go - they can take the most innocent thing and turn it into a buzz phrase, twisted to make you bad - to the world.
You would NOT enjoy living in your own house like a bug under a microscope -