However, the pair haven’t always got it right on the Channel 4 show, as one set of home-seekers tragically found out.
“We looked after a female couple who had two cats, which they adored,” Phil tells The Times (££).
“Kirstie found a house for these women and it was at a crossroads. They said, ‘We love the house, but we are worried about the cats and the road.’ Kirstie said confidently and brusquely that the cats would learn to live with it.
“A few years later I went back for a revisit, knocked at the door and said, ‘How are you, how are the cats?’ They had both been run over.”
Phil adds: “Luckily they got over it. They had a puppy.”
Kirstie says there have been plenty of surprises over the last twenty years too.
“After one episode my friend rang me and said, ‘That guy on your show last night works in my office and he is playing away from his wife.’ Statistically, though, we have a good track record. The people who go on Location stay together. We are the opposite of Hello! magazine.”
Another time a man who was wanted for fraud appeared on the programme. “He was arrested after the show went out,” Phil recalls. “His wife did not know. Why on earth he went on the show I do not know.”
After two decades of working together (and filming 237 episodes), the pair - who met for the first time at the screen test for the show - say their friendship is stronger than ever.
“Kirstie and I met on camera, and people have watched us become friends,” Phil says. “Our relationship has grown. It is not just work. Our little chats are never rehearsed — that’s what keeps it fresh. ”
“We only have each other,” Kirstie adds. “We have been on this journey together. Twenty years ago we had never been on TV. Now, taxi drivers, train conductors, everyone knows our name. We share this weird thing. I can’t fall out with Phil.”
Location, Location, Location: 20 Years and Counting airs on Wednesday on Channel 4.
This article originally appeared on HuffPost UK and has been updated.