Lynne and 'Mantha are out jogging. Lynne points out the Bladderwort-Smyths who are in a car. 'Mantha says she hears they are very rich, so much so that they own a huge place in the home counties. Lynne corrects her and tells her they own one of the home counties.
The Bladderwort-Smyths are an old couple who live nearby and drive around in a Rolls Royce. They are the scorn of the neighbourhood for flashing their wealth for all to see, but the actual extent of their wealth is shrouded in secrecy.
Chinese whispers have taken hold on the subject of the Bladderwort-Smyths. Some say they own Wimbledon, some say, as 'Mantha has heard, a huge place in the home counties. Lynne on the other hand has heard they own one of the home counties.
It is probably likely that Lynne is the sort of person who mishears something but takes it as fact. It is highly unlikely that they own one of the home counties. For this to happen they would have to approach the Queen and offer her a huge sum to take a whole county off her hands and it probably would have been on the news. The most likely explanation is that 'Mantha is correct, but Lynne is too stubborn to accept that and will stick by her story, even after she's been proved wrong.